The main source of energy for a star as it grows in size to become a red giant is

A main sequence star burns hydrogen to helium. Once a main sequence star exhausts all of the hydrogen, it begins to expand and burn helium causing if to become a red giant.

explanation:

earth's surface is mainly heated by the absorption of infrared radiation from the sun.

evaporation occurs because molecules in liquid water are warmed ( usually by the sun) and vibrate quicker, becoming less dense and rise.

condensation occurs because molecules in water vapor are cooled and therefore vibrate more slowly thus becoming more dense and eventually fall to earth.

lines of equal barometric pressure on a weather map are called: isobars : lines of equal temp on a weather map are called: isotherms.​

a longitudinal wave moves energy that is to the direction of the wave’s movement. - true