What is the most important part when passing a volleyball?

One object has a mass of 1 kg and another object has a mass of 3 kg. if the speeds are the same, which of the following is true about their kinetic energy?

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.

Which compound is held together by the electrostatic force between two ions? a. co2 b. cci4 c. h2s d. mgf2