Please help would be much appreciated:) Two of the key concepts of this Click-and-Learn activity are:

•Humans, like all species, are evolving and adapting to the environment.
•Natural selection acts on traits, but it affects the frequency of alleles in a population.

In essay format, explain these two concepts using examples from this Click and Learn.

correct answer is option a.

tropopause, stratopause and mesopause have all in common aspect that is point of maximum temperature in its layer of the atmosphere. all layers of atmosphere observe abrupt change in temperature. tropopause is the boundary between troposphere and stratosphere. stratopause is the boundary between stratosphere and mesosphere. mesopause is the boundary between mesosphere and thermosphere. these all boundaries are ranges between altitude of 0 to 80 km.

very

it is a. i hope this .