How does the idea of atoms
explain the principle of conservation of
matter?

Both the initial and final substances are composed of atoms because all matter is composed of atoms.

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.

answer; i believe the correct answer to the above question is ( friction)