The largest mass extinction was in the a. precambrian time. c. paleozoic era. b. cenozoic era. d. mesozoic era.

Asmall number of finches are removed randomly from the wild and placed in a protected bird area. they are given as much food as they need and have plenty of space. why would natural selection not occur in this population? a. there is no reason for genetic mutation to occur. b. the birds compete for limited resources, c. the population has not reached carrying capacity. d. there is no genetic variation in the finches.

If a strand of dna has 35% thymine. what is the percentage of cytosine, adenine, guanine?

How is the carbon cycle related to global warming ?