Researchers are able to directly measure the rate of productivity in experiments using a radioactively "tagged" atom
Which isotope is commonly used?
a. carbon-12
b. carbon-13
c. carbon-14
d. nitrogen-14
e. nitrogen-15
c
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In terms of number of deaths per participant, the most dangerous activity that most people in the U.S. participate in is
A. flying in an airplane. B. swimming in the ocean. C. riding in a motor vehicle. D. visiting a relative. E. walking in a thundershower.
A car has a mass of 1000 kg and accelerates at 2 m/s2. What is the magnitude of the force exerted on the car?
A) 500 N B) 1000 N C) 1500 N D) 2000 N E) none of the above
If an unsaturated air parcel with a temperature of 20oC rises, forms a non-precipitating cloud, then returns to its original altitude,
A) the parcel's final temperature will be less than 20 oC B) the parcel's final temperature will be exactly 20 oC C) the parcel's final temperature will be greater than 20 oC
Köppen's climate classification includes ________ major climate groups designated by capital letters
A) two B) four C) six D) eight E) ten