Which layer of the atmosphere correctly matches its description? A. The troposphere is the thickest layer of the atmosphere.

B. The mesosphere contains the warmest region of Earth's atmosphere.

C. The thermosphere is the coldest layer of the atmosphere as it is far away from Earth.

D. The stratosphere contains ozone which absorbs ultraviolet radiation in the atmosphere.

The characteristics of two different types of reactions are shown below: reaction a: electrons are gained by the atoms of an element. reaction b: protons are lost by the atom of an element. which statement is true about the atoms of the elements that participate in the two reactions? their identity changes in both reaction a and reaction b. their identity changes in reaction a but not in reaction b. their identity changes in reaction b but not in reaction a. their identity remains the same in both reaction a and reaction b.