Rocks in and on the earth are constantly changing because of both physical and chemical processes. the continual change in rocks on earth is called
a) erosion.
b) weathering.
c) the rock cycle.
d) the mineral cycle.

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.