Read the following passage and indicate the correct answer to each of the questions

The light bulb changed human existence by illuminating the night and making human activity possible in darkness. The electric light, one of the everyday conveniences that most affects our lives, was invented in 1879 by both Thomas Eva Edison in the United States, and Sir Joseph Wilson Swan in England at the same time. However, the story of the electric light actually goes back to 1811, when Sir Humphrey Davy discovered that an electrical arc passed between two poles produced light. In 1841, experimental lights were installed as public lighting along the Place de la Concorde in Paris. Other experiments were undertaken in Europe and America, but the arc light eventually proved impractical because it burned out too quickly. Inventors continued to work on the problem of developing a reliable electric light that would be practical for both home and public use instead of gas light. The solution lay not in electrical arc in open space, but in electricity passed through a filament. The breakthrough theory became known as the Joule effect after James Prescott Joule. He theorized that electrical current, if passed through a resistant conductor, would glow white-hot with heat energy and thus produce light. Edison decided to try a carbonized cotton thread filament. When voltage was applied to the completed bulb, it gave off a soft orange glow. Just about fifteen hours later, the filament finally burned out. Further experimentation produced filaments that could burn longer and longer with each test. By the end of 1880, he had produced a 10-watt bulb that could last for 1500 hours, and had begun to market his new invention. 

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