If a substance has a half-life of 5 million years, what fraction of the atoms remain after 10 million
years?
O A. 1/8
O B. 1/4
O C. 1/2
O D. 1/16

the three components of a nucleotide are the nitrogenous base, the phosphate group and the five-carbon sugar.

stimulus is a change in the environment that causes an organism to react. the response is the reaction to the stimulus. some examples of stimuli for zebras are drought, to many predators, and bad feeding grounds such as dead grass or plants. zebras respond to stimuli just like all other living organisms