It is said that "when we burn coal, we actually use the ancient solar energy". explain the meaning of this expression scientifically

If you visited mount shasta city (elevation 900 m [3000 ft.]) and found the outside air temperature to be 27°c (81°f), what would be the air temperature at the summit of mount shasta (elevation 4200 m [14,000 ft.]) at that moment-assuming that the temperature conditions with altitude change at an average, or normal, lapse rate?

What are high points of a transverse wave

If 2 different solids have the same masses but different volumes, how will their densities compare? a. the solids will have the same densities. b. the solid with lower volume will have a higher density. c. the solid with greater volume will have a higher density. d. the solid with greater volume will have double the density of the solid with the lower volume.