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Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions. For a time, the Hubble telescope was the brunt of jokes and subject to the wrath of those who believed the U.S government had spent too much money on space projects that served no valid purpose. The Hubble was sent into orbit with a satellite by the Space Shuttle Discovery in 1990 amid huge hype and expectation. Yet after it was in position, it simply did not work. Because the primary mirror was misshapen, it was not until 1993 that the crew of the Shuttle Endeavor arrived like roadside mechanics, opened the hatch that was installed for the purpose, and replaced the defective mirror with a good one. Suddenly, all that had originally been expected came true. The Hubble telescope was indeed the “window on the universe”, as it had originally been dubbed. When you look deep into space, you are actually looking back through time, because even though light travels at 186,000 miles a second, it requires time to get from one place to another. In fact, it is said that in some cases, the Hubble telescope is looking back eleven billion years to see galaxies already forming. The distant galaxies are speeding away from Earth, some travelling at the speed of light. Hubble has viewed exploding stars such as the Eta Carinae, which clearly displayed clouds of gas and dust billowing outward from its poles at 1.5 million miles an hour. Prior to Hubble, it was visible from traditional telescopes on Earth, but its details were not as certainable. But now, the evidence of the explosion is obvious. The star still burns five million times brighter than the Sun and illuminates clouds from the inside. Hubble has also provided a close look at black holes, which are described as comic drains. Gas and dust swirl around the drain and are slowly sucked in by the incredible gravity. It has also looked into an area that looked empty to the naked eye and, within a region the size of a grain of sand, located layer upon layer of galaxies, with each galaxy consisting of billions of stars. The Hubble telescope was named after Edwin Hubble, a 1920s astronomer who developed a formula that expresses the proportional relationship of distances between clusters of galaxies and the speeds at which they travel. Astronomers use stars known as Cepheid variables to measure distances in space. These stars dim and brighten from time to time, and they are photographed over time and charted. All the discoveries made by Hubble have allowed astronomers to learn more about the formation of early galaxiesThe author implies that a black hole is analogous to ________
Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions. For a time, the Hubble telescope was the brunt of jokes and subject to the wrath of those who believed the U.S government had spent too much money on space projects that served no valid purpose. The Hubble was sent into orbit with a satellite by the Space Shuttle Discovery in 1990 amid huge hype and expectation. Yet after it was in position, it simply did not work. Because the primary mirror was misshapen, it was not until 1993 that the crew of the Shuttle Endeavor arrived like roadside mechanics, opened the hatch that was installed for the purpose, and replaced the defective mirror with a good one. Suddenly, all that had originally been expected came true. The Hubble telescope was indeed the “window on the universe”, as it had originally been dubbed. When you look deep into space, you are actually looking back through time, because even though light travels at 186,000 miles a second, it requires time to get from one place to another. In fact, it is said that in some cases, the Hubble telescope is looking back eleven billion years to see galaxies already forming. The distant galaxies are speeding away from Earth, some travelling at the speed of light. Hubble has viewed exploding stars such as the Eta Carinae, which clearly displayed clouds of gas and dust billowing outward from its poles at 1.5 million miles an hour. Prior to Hubble, it was visible from traditional telescopes on Earth, but its details were not as certainable. But now, the evidence of the explosion is obvious. The star still burns five million times brighter than the Sun and illuminates clouds from the inside. Hubble has also provided a close look at black holes, which are described as comic drains. Gas and dust swirl around the drain and are slowly sucked in by the incredible gravity. It has also looked into an area that looked empty to the naked eye and, within a region the size of a grain of sand, located layer upon layer of galaxies, with each galaxy consisting of billions of stars. The Hubble telescope was named after Edwin Hubble, a 1920s astronomer who developed a formula that expresses the proportional relationship of distances between clusters of galaxies and the speeds at which they travel. Astronomers use stars known as Cepheid variables to measure distances in space. These stars dim and brighten from time to time, and they are photographed over time and charted. All the discoveries made by Hubble have allowed astronomers to learn more about the formation of early galaxiesThe word “billowing” in the third paragraph is closest meaning to ________ 
Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions. For a time, the Hubble telescope was the brunt of jokes and subject to the wrath of those who believed the U.S government had spent too much money on space projects that served no valid purpose. The Hubble was sent into orbit with a satellite by the Space Shuttle Discovery in 1990 amid huge hype and expectation. Yet after it was in position, it simply did not work. Because the primary mirror was misshapen, it was not until 1993 that the crew of the Shuttle Endeavor arrived like roadside mechanics, opened the hatch that was installed for the purpose, and replaced the defective mirror with a good one. Suddenly, all that had originally been expected came true. The Hubble telescope was indeed the “window on the universe”, as it had originally been dubbed. When you look deep into space, you are actually looking back through time, because even though light travels at 186,000 miles a second, it requires time to get from one place to another. In fact, it is said that in some cases, the Hubble telescope is looking back eleven billion years to see galaxies already forming. The distant galaxies are speeding away from Earth, some travelling at the speed of light. Hubble has viewed exploding stars such as the Eta Carinae, which clearly displayed clouds of gas and dust billowing outward from its poles at 1.5 million miles an hour. Prior to Hubble, it was visible from traditional telescopes on Earth, but its details were not as certainable. But now, the evidence of the explosion is obvious. The star still burns five million times brighter than the Sun and illuminates clouds from the inside. Hubble has also provided a close look at black holes, which are described as comic drains. Gas and dust swirl around the drain and are slowly sucked in by the incredible gravity. It has also looked into an area that looked empty to the naked eye and, within a region the size of a grain of sand, located layer upon layer of galaxies, with each galaxy consisting of billions of stars. The Hubble telescope was named after Edwin Hubble, a 1920s astronomer who developed a formula that expresses the proportional relationship of distances between clusters of galaxies and the speeds at which they travel. Astronomers use stars known as Cepheid variables to measure distances in space. These stars dim and brighten from time to time, and they are photographed over time and charted. All the discoveries made by Hubble have allowed astronomers to learn more about the formation of early galaxiesThe author states that ________
Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions. For a time, the Hubble telescope was the brunt of jokes and subject to the wrath of those who believed the U.S government had spent too much money on space projects that served no valid purpose. The Hubble was sent into orbit with a satellite by the Space Shuttle Discovery in 1990 amid huge hype and expectation. Yet after it was in position, it simply did not work. Because the primary mirror was misshapen, it was not until 1993 that the crew of the Shuttle Endeavor arrived like roadside mechanics, opened the hatch that was installed for the purpose, and replaced the defective mirror with a good one. Suddenly, all that had originally been expected came true. The Hubble telescope was indeed the “window on the universe”, as it had originally been dubbed. When you look deep into space, you are actually looking back through time, because even though light travels at 186,000 miles a second, it requires time to get from one place to another. In fact, it is said that in some cases, the Hubble telescope is looking back eleven billion years to see galaxies already forming. The distant galaxies are speeding away from Earth, some travelling at the speed of light. Hubble has viewed exploding stars such as the Eta Carinae, which clearly displayed clouds of gas and dust billowing outward from its poles at 1.5 million miles an hour. Prior to Hubble, it was visible from traditional telescopes on Earth, but its details were not as certainable. But now, the evidence of the explosion is obvious. The star still burns five million times brighter than the Sun and illuminates clouds from the inside. Hubble has also provided a close look at black holes, which are described as comic drains. Gas and dust swirl around the drain and are slowly sucked in by the incredible gravity. It has also looked into an area that looked empty to the naked eye and, within a region the size of a grain of sand, located layer upon layer of galaxies, with each galaxy consisting of billions of stars. The Hubble telescope was named after Edwin Hubble, a 1920s astronomer who developed a formula that expresses the proportional relationship of distances between clusters of galaxies and the speeds at which they travel. Astronomers use stars known as Cepheid variables to measure distances in space. These stars dim and brighten from time to time, and they are photographed over time and charted. All the discoveries made by Hubble have allowed astronomers to learn more about the formation of early galaxiesThe author states that Edward Hubble ________
Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions. For a time, the Hubble telescope was the brunt of jokes and subject to the wrath of those who believed the U.S government had spent too much money on space projects that served no valid purpose. The Hubble was sent into orbit with a satellite by the Space Shuttle Discovery in 1990 amid huge hype and expectation. Yet after it was in position, it simply did not work. Because the primary mirror was misshapen, it was not until 1993 that the crew of the Shuttle Endeavor arrived like roadside mechanics, opened the hatch that was installed for the purpose, and replaced the defective mirror with a good one. Suddenly, all that had originally been expected came true. The Hubble telescope was indeed the “window on the universe”, as it had originally been dubbed. When you look deep into space, you are actually looking back through time, because even though light travels at 186,000 miles a second, it requires time to get from one place to another. In fact, it is said that in some cases, the Hubble telescope is looking back eleven billion years to see galaxies already forming. The distant galaxies are speeding away from Earth, some travelling at the speed of light. Hubble has viewed exploding stars such as the Eta Carinae, which clearly displayed clouds of gas and dust billowing outward from its poles at 1.5 million miles an hour. Prior to Hubble, it was visible from traditional telescopes on Earth, but its details were not as certainable. But now, the evidence of the explosion is obvious. The star still burns five million times brighter than the Sun and illuminates clouds from the inside. Hubble has also provided a close look at black holes, which are described as comic drains. Gas and dust swirl around the drain and are slowly sucked in by the incredible gravity. It has also looked into an area that looked empty to the naked eye and, within a region the size of a grain of sand, located layer upon layer of galaxies, with each galaxy consisting of billions of stars. The Hubble telescope was named after Edwin Hubble, a 1920s astronomer who developed a formula that expresses the proportional relationship of distances between clusters of galaxies and the speeds at which they travel. Astronomers use stars known as Cepheid variables to measure distances in space. These stars dim and brighten from time to time, and they are photographed over time and charted. All the discoveries made by Hubble have allowed astronomers to learn more about the formation of early galaxiesThe word “it” in paragraph 1 refers to ______
Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions. For a time, the Hubble telescope was the brunt of jokes and subject to the wrath of those who believed the U.S government had spent too much money on space projects that served no valid purpose. The Hubble was sent into orbit with a satellite by the Space Shuttle Discovery in 1990 amid huge hype and expectation. Yet after it was in position, it simply did not work. Because the primary mirror was misshapen, it was not until 1993 that the crew of the Shuttle Endeavor arrived like roadside mechanics, opened the hatch that was installed for the purpose, and replaced the defective mirror with a good one. Suddenly, all that had originally been expected came true. The Hubble telescope was indeed the “window on the universe”, as it had originally been dubbed. When you look deep into space, you are actually looking back through time, because even though light travels at 186,000 miles a second, it requires time to get from one place to another. In fact, it is said that in some cases, the Hubble telescope is looking back eleven billion years to see galaxies already forming. The distant galaxies are speeding away from Earth, some travelling at the speed of light. Hubble has viewed exploding stars such as the Eta Carinae, which clearly displayed clouds of gas and dust billowing outward from its poles at 1.5 million miles an hour. Prior to Hubble, it was visible from traditional telescopes on Earth, but its details were not as certainable. But now, the evidence of the explosion is obvious. The star still burns five million times brighter than the Sun and illuminates clouds from the inside. Hubble has also provided a close look at black holes, which are described as comic drains. Gas and dust swirl around the drain and are slowly sucked in by the incredible gravity. It has also looked into an area that looked empty to the naked eye and, within a region the size of a grain of sand, located layer upon layer of galaxies, with each galaxy consisting of billions of stars. The Hubble telescope was named after Edwin Hubble, a 1920s astronomer who developed a formula that expresses the proportional relationship of distances between clusters of galaxies and the speeds at which they travel. Astronomers use stars known as Cepheid variables to measure distances in space. These stars dim and brighten from time to time, and they are photographed over time and charted. All the discoveries made by Hubble have allowed astronomers to learn more about the formation of early galaxiesThe author compares the astronauts of the Endeavor to ________ 
Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions. For a time, the Hubble telescope was the brunt of jokes and subject to the wrath of those who believed the U.S government had spent too much money on space projects that served no valid purpose. The Hubble was sent into orbit with a satellite by the Space Shuttle Discovery in 1990 amid huge hype and expectation. Yet after it was in position, it simply did not work. Because the primary mirror was misshapen, it was not until 1993 that the crew of the Shuttle Endeavor arrived like roadside mechanics, opened the hatch that was installed for the purpose, and replaced the defective mirror with a good one. Suddenly, all that had originally been expected came true. The Hubble telescope was indeed the “window on the universe”, as it had originally been dubbed. When you look deep into space, you are actually looking back through time, because even though light travels at 186,000 miles a second, it requires time to get from one place to another. In fact, it is said that in some cases, the Hubble telescope is looking back eleven billion years to see galaxies already forming. The distant galaxies are speeding away from Earth, some travelling at the speed of light. Hubble has viewed exploding stars such as the Eta Carinae, which clearly displayed clouds of gas and dust billowing outward from its poles at 1.5 million miles an hour. Prior to Hubble, it was visible from traditional telescopes on Earth, but its details were not as certainable. But now, the evidence of the explosion is obvious. The star still burns five million times brighter than the Sun and illuminates clouds from the inside. Hubble has also provided a close look at black holes, which are described as comic drains. Gas and dust swirl around the drain and are slowly sucked in by the incredible gravity. It has also looked into an area that looked empty to the naked eye and, within a region the size of a grain of sand, located layer upon layer of galaxies, with each galaxy consisting of billions of stars. The Hubble telescope was named after Edwin Hubble, a 1920s astronomer who developed a formula that expresses the proportional relationship of distances between clusters of galaxies and the speeds at which they travel. Astronomers use stars known as Cepheid variables to measure distances in space. These stars dim and brighten from time to time, and they are photographed over time and charted. All the discoveries made by Hubble have allowed astronomers to learn more about the formation of early galaxiesThe author implies that the satellite that carries the Hubble was specifically designed so that _________
Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions. For a time, the Hubble telescope was the brunt of jokes and subject to the wrath of those who believed the U.S government had spent too much money on space projects that served no valid purpose. The Hubble was sent into orbit with a satellite by the Space Shuttle Discovery in 1990 amid huge hype and expectation. Yet after it was in position, it simply did not work. Because the primary mirror was misshapen, it was not until 1993 that the crew of the Shuttle Endeavor arrived like roadside mechanics, opened the hatch that was installed for the purpose, and replaced the defective mirror with a good one. Suddenly, all that had originally been expected came true. The Hubble telescope was indeed the “window on the universe”, as it had originally been dubbed. When you look deep into space, you are actually looking back through time, because even though light travels at 186,000 miles a second, it requires time to get from one place to another. In fact, it is said that in some cases, the Hubble telescope is looking back eleven billion years to see galaxies already forming. The distant galaxies are speeding away from Earth, some travelling at the speed of light. Hubble has viewed exploding stars such as the Eta Carinae, which clearly displayed clouds of gas and dust billowing outward from its poles at 1.5 million miles an hour. Prior to Hubble, it was visible from traditional telescopes on Earth, but its details were not as certainable. But now, the evidence of the explosion is obvious. The star still burns five million times brighter than the Sun and illuminates clouds from the inside. Hubble has also provided a close look at black holes, which are described as comic drains. Gas and dust swirl around the drain and are slowly sucked in by the incredible gravity. It has also looked into an area that looked empty to the naked eye and, within a region the size of a grain of sand, located layer upon layer of galaxies, with each galaxy consisting of billions of stars. The Hubble telescope was named after Edwin Hubble, a 1920s astronomer who developed a formula that expresses the proportional relationship of distances between clusters of galaxies and the speeds at which they travel. Astronomers use stars known as Cepheid variables to measure distances in space. These stars dim and brighten from time to time, and they are photographed over time and charted. All the discoveries made by Hubble have allowed astronomers to learn more about the formation of early galaxiesThe author states that the Hubble was not always popular because ________.
Read the passage below and choose the best answers that follow. Millions of people are using cell phones today. In many places, it is actually considered unusual not to use one. In many countries, cell phones are very popular with young people. They find that the phones are more than a means of communication - having a mobile phone shows that they are cool and connected. The explosion in mobile phone use around the world has made some health professionals worried. Some doctors are concerned that in the future many people may suffer health problems from the use of mobile phones. In England, there has been a serious debate about this issue. Mobile phone companies are worried about the negative publicity of such ideas. They say that there is no proof that mobile phones are bad for your health.On the other hand, medical studies have shown changes in the brain cells of some people who use mobile phones. Signs of change in the tissues of the brain and head can be detected with modern scanning equipment. In one case, a traveling salesman had to retire at young age because of serious memory loss. He couldn't remember even simple tasks. He would often forget the name of his own son. This man used to talk on his mobile phone for about six hours a day, every day of his working week, for a couple of years. His family doctor blamed his mobile phone use, but his employer's doctor didn't agree. What is it that makes mobile phones potentially harmful? The answer is radiation. High-tech machines can detect very small amounts of radiation from mobile phones. Mobile phone companies agree that there is some radiation, but they say the amount is too small to worry about. As the discussion about their safety continues, it appears that it's best to use mobile phones less often. Use your regular phone if you want to talk for a long time. Use your mobile phone only when you really need it. Mobile phones can be very useful and convenient, especially in emergencies. In the future, mobile phones may have a warning label that says they are bad for your health. So for now, it's wise not to use your mobile phone too oftenThe most suitable title for the passage could be _______ 
Read the passage below and choose the best answers that follow. Millions of people are using cell phones today. In many places, it is actually considered unusual not to use one. In many countries, cell phones are very popular with young people. They find that the phones are more than a means of communication - having a mobile phone shows that they are cool and connected. The explosion in mobile phone use around the world has made some health professionals worried. Some doctors are concerned that in the future many people may suffer health problems from the use of mobile phones. In England, there has been a serious debate about this issue. Mobile phone companies are worried about the negative publicity of such ideas. They say that there is no proof that mobile phones are bad for your health.On the other hand, medical studies have shown changes in the brain cells of some people who use mobile phones. Signs of change in the tissues of the brain and head can be detected with modern scanning equipment. In one case, a traveling salesman had to retire at young age because of serious memory loss. He couldn't remember even simple tasks. He would often forget the name of his own son. This man used to talk on his mobile phone for about six hours a day, every day of his working week, for a couple of years. His family doctor blamed his mobile phone use, but his employer's doctor didn't agree. What is it that makes mobile phones potentially harmful? The answer is radiation. High-tech machines can detect very small amounts of radiation from mobile phones. Mobile phone companies agree that there is some radiation, but they say the amount is too small to worry about. As the discussion about their safety continues, it appears that it's best to use mobile phones less often. Use your regular phone if you want to talk for a long time. Use your mobile phone only when you really need it. Mobile phones can be very useful and convenient, especially in emergencies. In the future, mobile phones may have a warning label that says they are bad for your health. So for now, it's wise not to use your mobile phone too oftenThe word "potentially" in the passage most closely means .................... 
Read the passage below and choose the best answers that follow. Millions of people are using cell phones today. In many places, it is actually considered unusual not to use one. In many countries, cell phones are very popular with young people. They find that the phones are more than a means of communication - having a mobile phone shows that they are cool and connected. The explosion in mobile phone use around the world has made some health professionals worried. Some doctors are concerned that in the future many people may suffer health problems from the use of mobile phones. In England, there has been a serious debate about this issue. Mobile phone companies are worried about the negative publicity of such ideas. They say that there is no proof that mobile phones are bad for your health.On the other hand, medical studies have shown changes in the brain cells of some people who use mobile phones. Signs of change in the tissues of the brain and head can be detected with modern scanning equipment. In one case, a traveling salesman had to retire at young age because of serious memory loss. He couldn't remember even simple tasks. He would often forget the name of his own son. This man used to talk on his mobile phone for about six hours a day, every day of his working week, for a couple of years. His family doctor blamed his mobile phone use, but his employer's doctor didn't agree. What is it that makes mobile phones potentially harmful? The answer is radiation. High-tech machines can detect very small amounts of radiation from mobile phones. Mobile phone companies agree that there is some radiation, but they say the amount is too small to worry about. As the discussion about their safety continues, it appears that it's best to use mobile phones less often. Use your regular phone if you want to talk for a long time. Use your mobile phone only when you really need it. Mobile phones can be very useful and convenient, especially in emergencies. In the future, mobile phones may have a warning label that says they are bad for your health. So for now, it's wise not to use your mobile phone too oftenThe word “they” in paragraph 1 refers to ______.
Read the passage below and choose the best answers that follow. Millions of people are using cell phones today. In many places, it is actually considered unusual not to use one. In many countries, cell phones are very popular with young people. They find that the phones are more than a means of communication - having a mobile phone shows that they are cool and connected. The explosion in mobile phone use around the world has made some health professionals worried. Some doctors are concerned that in the future many people may suffer health problems from the use of mobile phones. In England, there has been a serious debate about this issue. Mobile phone companies are worried about the negative publicity of such ideas. They say that there is no proof that mobile phones are bad for your health.On the other hand, medical studies have shown changes in the brain cells of some people who use mobile phones. Signs of change in the tissues of the brain and head can be detected with modern scanning equipment. In one case, a traveling salesman had to retire at young age because of serious memory loss. He couldn't remember even simple tasks. He would often forget the name of his own son. This man used to talk on his mobile phone for about six hours a day, every day of his working week, for a couple of years. His family doctor blamed his mobile phone use, but his employer's doctor didn't agree. What is it that makes mobile phones potentially harmful? The answer is radiation. High-tech machines can detect very small amounts of radiation from mobile phones. Mobile phone companies agree that there is some radiation, but they say the amount is too small to worry about. As the discussion about their safety continues, it appears that it's best to use mobile phones less often. Use your regular phone if you want to talk for a long time. Use your mobile phone only when you really need it. Mobile phones can be very useful and convenient, especially in emergencies. In the future, mobile phones may have a warning label that says they are bad for your health. So for now, it's wise not to use your mobile phone too oftenThe man mentioned in the passage, who used his cell phone too often, _______
Read the passage below and choose the best answers that follow. Millions of people are using cell phones today. In many places, it is actually considered unusual not to use one. In many countries, cell phones are very popular with young people. They find that the phones are more than a means of communication - having a mobile phone shows that they are cool and connected. The explosion in mobile phone use around the world has made some health professionals worried. Some doctors are concerned that in the future many people may suffer health problems from the use of mobile phones. In England, there has been a serious debate about this issue. Mobile phone companies are worried about the negative publicity of such ideas. They say that there is no proof that mobile phones are bad for your health.On the other hand, medical studies have shown changes in the brain cells of some people who use mobile phones. Signs of change in the tissues of the brain and head can be detected with modern scanning equipment. In one case, a traveling salesman had to retire at young age because of serious memory loss. He couldn't remember even simple tasks. He would often forget the name of his own son. This man used to talk on his mobile phone for about six hours a day, every day of his working week, for a couple of years. His family doctor blamed his mobile phone use, but his employer's doctor didn't agree. What is it that makes mobile phones potentially harmful? The answer is radiation. High-tech machines can detect very small amounts of radiation from mobile phones. Mobile phone companies agree that there is some radiation, but they say the amount is too small to worry about. As the discussion about their safety continues, it appears that it's best to use mobile phones less often. Use your regular phone if you want to talk for a long time. Use your mobile phone only when you really need it. Mobile phones can be very useful and convenient, especially in emergencies. In the future, mobile phones may have a warning label that says they are bad for your health. So for now, it's wise not to use your mobile phone too oftenThe changes possibly caused by the cell phones are mainly concerned with ______
Read the passage below and choose the best answers that follow. Millions of people are using cell phones today. In many places, it is actually considered unusual not to use one. In many countries, cell phones are very popular with young people. They find that the phones are more than a means of communication - having a mobile phone shows that they are cool and connected. The explosion in mobile phone use around the world has made some health professionals worried. Some doctors are concerned that in the future many people may suffer health problems from the use of mobile phones. In England, there has been a serious debate about this issue. Mobile phone companies are worried about the negative publicity of such ideas. They say that there is no proof that mobile phones are bad for your health.On the other hand, medical studies have shown changes in the brain cells of some people who use mobile phones. Signs of change in the tissues of the brain and head can be detected with modern scanning equipment. In one case, a traveling salesman had to retire at young age because of serious memory loss. He couldn't remember even simple tasks. He would often forget the name of his own son. This man used to talk on his mobile phone for about six hours a day, every day of his working week, for a couple of years. His family doctor blamed his mobile phone use, but his employer's doctor didn't agree. What is it that makes mobile phones potentially harmful? The answer is radiation. High-tech machines can detect very small amounts of radiation from mobile phones. Mobile phone companies agree that there is some radiation, but they say the amount is too small to worry about. As the discussion about their safety continues, it appears that it's best to use mobile phones less often. Use your regular phone if you want to talk for a long time. Use your mobile phone only when you really need it. Mobile phones can be very useful and convenient, especially in emergencies. In the future, mobile phones may have a warning label that says they are bad for your health. So for now, it's wise not to use your mobile phone too often"Negative publicity" in the passage most likely means __________ 
Read the passage below and choose the best answers that follow. Millions of people are using cell phones today. In many places, it is actually considered unusual not to use one. In many countries, cell phones are very popular with young people. They find that the phones are more than a means of communication - having a mobile phone shows that they are cool and connected. The explosion in mobile phone use around the world has made some health professionals worried. Some doctors are concerned that in the future many people may suffer health problems from the use of mobile phones. In England, there has been a serious debate about this issue. Mobile phone companies are worried about the negative publicity of such ideas. They say that there is no proof that mobile phones are bad for your health.On the other hand, medical studies have shown changes in the brain cells of some people who use mobile phones. Signs of change in the tissues of the brain and head can be detected with modern scanning equipment. In one case, a traveling salesman had to retire at young age because of serious memory loss. He couldn't remember even simple tasks. He would often forget the name of his own son. This man used to talk on his mobile phone for about six hours a day, every day of his working week, for a couple of years. His family doctor blamed his mobile phone use, but his employer's doctor didn't agree. What is it that makes mobile phones potentially harmful? The answer is radiation. High-tech machines can detect very small amounts of radiation from mobile phones. Mobile phone companies agree that there is some radiation, but they say the amount is too small to worry about. As the discussion about their safety continues, it appears that it's best to use mobile phones less often. Use your regular phone if you want to talk for a long time. Use your mobile phone only when you really need it. Mobile phones can be very useful and convenient, especially in emergencies. In the future, mobile phones may have a warning label that says they are bad for your health. So for now, it's wise not to use your mobile phone too oftenAccording to the passage, cell phones are especially popular with young people because _______