This task is about writing a correct answer for the reading comprehension task. Based on the information provided in a given passage, you should identify the shortest continuous text span from the passage that serves as an answer to the given question. Avoid answers that are incorrect or provides incomplete justification for the question.

[Q]: Passage: Mach argued that, in effect, the water experiment in an otherwise empty universe would remain flat. But if another object were introduced into this universe, perhaps a distant star, there would now be something relative to which the bucket could be seen as rotating. The water inside the bucket could possibly have a slight curve. To account for the curve that we observe, an increase in the number of objects in the universe also increases the curvature in the water. Mach argued that the momentum of an object, whether angular or linear, exists as a result of the sum of the effects of other objects in the universe (Mach's Principle). Question: Mach argued that the momentum of an object exists as a result of the sum of the effects of what?
[A]: effects of other objects in the universe


[Q]: Passage: North Carolina's party loyalties have undergone a series of important shifts in the last few years: While the 2010 midterms saw Tar Heel voters elect a bicameral Republican majority legislature for the first time in over a century, North Carolina has also become a Southern swing state in presidential races. Since Southern Democrat Jimmy Carter's comfortable victory in the state in 1976, the state had consistently leaned Republican in presidential elections until Democrat Barack Obama narrowly won the state in 2008. In the 1990s, Democrat Bill Clinton came within a point of winning the state in 1992 and also only narrowly lost the state in 1996. In the early 2000s, Republican George W. Bush easily won the state by over 12 points, but by 2008, demographic shifts, population growth, and increased liberalization in heavily populated areas such as the Research Triangle, Charlotte, Greensboro, Winston-Salem, Fayetteville, and Asheville, propelled Barack Obama to victory in North Carolina, the first Democrat to win the state since 1976. In 2012, North Carolina was again considered a competitive swing state, with the Democrats even holding their 2012 Democratic National Convention in Charlotte. However, Republican Mitt Romney ultimately eked out a 2-point win in North Carolina, the only 2012 swing state that Obama lost, and one of only two states (along with Indiana) to flip from Obama in 2008 to the GOP in 2012. Question: What year did Bill Clinton lose North Carolina?
[A]: 1996


[Q]: Passage: Geography effects solar energy potential because areas that are closer to the equator have a greater amount of solar radiation. However, the use of photovoltaics that can follow the position of the sun can significantly increase the solar energy potential in areas that are farther from the equator. Time variation effects the potential of solar energy because during the nighttime there is little solar radiation on the surface of the Earth for solar panels to absorb. This limits the amount of energy that solar panels can absorb in one day. Cloud cover can effect the potential of solar panels because clouds block incoming light from the sun and reduce the light available for solar cells. Question: Why does time have an effect of the amount of available solar energy?
[A]:
during the nighttime there is little solar radiation on the surface of the Earth for solar panels to absorb