If 1.00 km^3 of air has a mass of 1.2x10^9 kg what is the density of air in g/cm^3

Order the sequence of ideas that lead to marie curies discovery of radioactive elements number the events in chronological order starting with the oldest

A2-kg bowling ball is 2.5 meters off the ground on a post when it falls. just before it reaches the ground, it is traveling 7 m/s. assuming that there is no air resistance, which statement is true?

What organization and environment is described above?