The problem: Answer a question about this article:
Mark Z. Jacobson, professor of civil and environmental engineering at Stanford University and director of its Atmosphere and Energy Program says producing all new energy with wind power, solar power, and hydropower by 2030 is feasible and existing energy supply arrangements could be replaced by 2050. Barriers to implementing the renewable energy plan are seen to be "primarily social and political, not technological or economic". Jacobson says that energy costs with a wind, solar, water system should be similar to today's energy costs.
What is a barrier to implementing the renewable energy plan?
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The answer: social and political


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The Bell Telephone Company was created in 1877, and by 1886, more than 150,000 people in the U.S. owned telephones. Bell Company engineers made numerous other improvements to the telephone, which emerged as one of the most successful products ever. In 1879, the Bell company acquired Edison's patents for the carbon microphone from Western Union. This made the telephone practical for longer distances, and it was no longer necessary to shout to be heard at the receiving telephone.
What addition let people stop yelling into the telephone?
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The answer: carbon microphone


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One wave of the population boom ended abruptly in the mid-1980s, as oil prices fell precipitously. The space industry also suffered in 1986 after the Space Shuttle Challenger disintegrated shortly after launch. There was a cutback in some activities for a period. In the late 1980s, the city's economy suffered from the nationwide recession. After the early 1990s recession, Houston made efforts to diversify its economy by focusing on aerospace and health care/biotechnology, and reduced its dependence on the petroleum industry. Since the increase of oil prices in the 2000s, the petroleum industry has again increased its share of the local economy.
What did Houston focus on after the 1990s recession to improve its economy?
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The answer: aerospace and health care


The problem: Answer a question about this article:
Season eight premiered on January 13, 2009. Mike Darnell, the president of alternative programming for Fox, stated that the season would focus more on the contestants' personal life. Much early attention on the show was therefore focused on the widowhood of Danny Gokey.[citation needed]
Who was the president of alternative programming at Fox?
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The answer:
Mike Darnell