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Choose the correct answer for the questionOf the six outer planets, Mars, commonly called the red planet, is the closest to Earth. Mars, 4,200 miles in diameter and 55 percent of the size of Earth, is 34,600,000 miles from Earth, and 141,000,000 miles from the Sun. It takes this planet, along with its two moons, Phobos and Deimos, 1.88 years to circle the Sun, compared to 365 days for the Earth. For many years, Mars had been thought of as the planet with the man-made canals, supposedly discovered by an Italian astronomer, Schiaparelli, in 1877. With the United States spacecraft Viking I's landing on Mars in 1976, the man-made canal theory was proven to be only a myth. Viking I, after landing on the soil of Mars, performed many scientific experiments and took numerous pictures. The pictures showed that the red color of the planet is due to the reddish, rocky Martian soil. No biological life was found, though it had been speculated by many scientists. The Viking also monitored many weather changes including violent dust storms. Some water vapor, polar ice, and permafrost (frost below the surface) were found, indicating that at one time there were significant quantities of water on this distant planet. Evidence collected by the spacecraft shows some present volcanic action, though the volcanoes are believed to be dormant, if not extinct.All of the following are true EXCEPT ______

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Read the passage and choose the correct answer The biologist's role in society as well as his moral and ethical responsibility in the discovery and development of new ideas has led to a reassessment of his social and scientific value systems. A scientist can no longer ignore the consequences of his discoveries; he is as concerned with the possible misuses of his findings as he is with the basic research in which he is involved. This emerging social and political role of the biologist and all other scientists requires a weighing of values that cannot be done with the accuracy or the objectivity of a laboratory balance. As a member of society, it is necessary for a biologist now to redefine his social obligations and his functions, particularly in the realm of making judgments about such ethical problems as man's control of his environment or his manipulation of genes to direct further evolutionary development. As a result of recent discoveries concerning hereditary mechanisms, genetic engineering, by which human traits are made to order, may soon be a reality. As desirable as it may seem to be, such an accomplishment would entail many value judgments. Who would decide, for example, which traits should be selected for change? In cases of genetic deficiencies and disease, the desirability of the change is obvious, but the possibilities for social misuse are so numerous that may far outweigh the benefits. Probably the greatest biological problem of the future, as it is of the present, will be to find ways to curb environmental pollution without interfering with man's constant effort to improve the quality of his life. According to the passage, a modem scientist should be more concerned about____.

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