[单项选择]How do the scientists measure the pitch
A. According to the movement and vibrations of hot gasses.
B. The trade winds blow on Earth.
C. The rivers.
D. The sound travel through the space.

[单项选择]How do the scientists measure the pitch
A. According to the movement and vibrations of hot gasses
B. The trade winds blow on Earth
C. The rivers
D. The sound travel through the space

[单项选择]How exactly, does science work How do scientists go about doing science Ordinarily we think science proceeds in a straight-forward way. Ideally scientists make observations, formulate hypotheses (假设), and test those hypotheses by making further observations. When there is difference between what is observed and what is predicted by the hypothesis, the hypothesis is revised. Science proceeds in this way, which is a gradual method of finding the best fit between observation and prediction.
But this idealized version of how one does science is naive. Although science demands proof that observations made by one observer be observable by other observers using the same methods, it is by no means dear that, even when confronted with identical phenomena, different observers will report identical observations. And it is most certain that, even if the same observations are made, the conclusions as to the meaning of the observations frequently differ.
The fact is that all of us, s
A. The research methods used by scientists.
B. Observation and human perception variation.
C. The relation between hypothesis and observation.
D. The human perceptual mechanism.

[单项选择]Passage 1 Liquidity is a measure of how quickly an item may be converted to cash. Therefore, cash is the most liquid asset. Account receivable is a relatively liquid asset because the business expects to collect the amount in cash in the near future. Supplies are less liquid than accounts receivable. Users of financial statements are interested in liquidity because business difficulties often arise owing to shortage of cash. How quickly can the business convert an asset to cash and pay a debt How soon must a liability be paid These are questions of liquidity.Long-term assets are all assets other than current assets.
A. right
B. wrong
C. Doesn’t say

[单项选择]

How do we measure the economic return to higher education Typically it is calculated as the difference between average wages of college graduates and those who have not graduated from college. In 1997, for example, college graduates earned an average of $ 40, 508 versus just $ 23, 970 for non-college graduates. Based on these income levels, the economic return to a college education is approximately 69 percent, the difference between the two income levels. But this simple calculation ignores the fact that college graduates tend to come from higher socioeconomic levels, are more highly motivated, and probably have higher IQs than nongraduates. Although these factors influence incomes, they are not the result of college attendance. Therefore the result of the study is an overstatement of the returns to higher education.
More sophisticated analyses adjust for these extraneous influences. For instance economists Orley Ashenfelter and Alan Krueger, estimate that each year of p
A. it doesn’t take into account the changing economic situations
B. it involves small samples
C. it failed to incorporate some aspects which themselves might have added to the earnings of college graduates
D. it does not specify whether non-college graduates have high-school degrees

[简答题]In fact, scientists do not fully understand how the memory works but they have not shown that there is any limit to the amount of information that the human brain can store.

[单项选择]Citizen Scientists 　　Understanding how nature responds to climate change will require monitoring key life cycle events — flowering, the appearance of leaves, the first frog calls of the spring — all around the world. But ecologists can’t be(51) so they’re turning to non-scientists, sometimes called citizen scientists, for help. 　　Climate scientists are not present everywhere.(52) there are so many places in the world and not enough scientists to observe all of them, they’re asking for your help in(53) signs of climate change across the world. The citizen scientist movement encourages(54) people to observe a very specific research interest — birds, trees, flowers budding, etc. — and send their observations(55) a giant database to be observed by professional scientists. This helps a small number of scientists track a(56) amount of data that they would never be able to gather on their own.(57) like citizen journalists helping large publications cover a hyper-local beat, citizen scientis
A. points
B. wonders
C. data
D. interests