Air above the equator is heated more than at any other place on earth because solar rays strike the equator
a. at a 180° angle
c. more directly
b. at a 45° angle
d. none of the above

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?