Find the magnitude of the gravitational force a 68.4 kg person would experience while standing on the surface of earth with a mass of 5.98 ã 1024 kg and a radius of 6.37 ã 106 m. the universal gravitational constant is 6.673 ã 10â11 n â· m2 /kg2 . answer in units of n.

Assume that a person skiing high in the mountains at an altitude of h = 15100 ft takes in the same volume of air with each breath as she does while walking at sea level. determine the ratio of the mass of oxygen inhaled for each breath at this high altitude compared to that at sea level. assume that the air composition (i.e. % of air that is oxygen) is the same at sea level as it is at 15100 ft.