Heat is a transfer of thermal energy from one object to anther because of a difference in?

Why does karst topography exist in some geographic location? a. few climates have enough oxygen b. most regions have rock layers other than limestone c. in most regions, the soil is too thin d. the water is too acidic enough in most places

Four friends, a, b, c, and d are standing varying distances away from a speaker which is producing sound waves.

Ihave this 50 question test the layer of earth's atmosphere where atoms and molecules escape into space is referred to as the a) exosphere b) ionosphere. c) mesosphere d) thermosphere