Light is emitted as an electron transitions from a higher energy state to a lower energy state. How long does it take for the actual transition to take place?
A. several seconds
B. several nanoseconds
C. several microseconds
D. no time at all
Answer: D
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Which of the following is not a current effect of climate change?
A. There are new species of mammals observed in the Arctic resembling camels. B. Sea ice is at a record low. C. Sea level has risen measurably. D. There is a general trend that flowers are blooming earlier in the spring.
Range zones ____
a. are formations that are lithologically similar b. consist of one rock layer c. consist of one rock type d. represent periods of time over which lithologically similar rocks are deposited e. mark the first and last appearance of a fossil
Why is humid air less dense than dry air?
a. Molecular movement of water vapor occupies less space than dry air. b. Molecular movement of water vapor occupies more space than dry air. c. Water vapor molecules are more compressed than dry air molecules. d. Molecules of water vapor have less mass than the displaced nitrogen and oxygen. e. Molecules of water vapor have more mass than the displaced nitrogen and oxygen.
Manganese and phosphorite nodules can only be observed in areas of high sediment accumulation. Indicate whether the statement is true or false