An astronaut on the Moon releases a rock from rest and allows it to drop straight downward. If the acceleration due to gravity on the Moon is 1.62m/s2 and the rock falls for 2.4s before hitting the ground, what is its speed just before it lands?

Air initially at 0.75 bar, 1000 k, and occupying a volume of 0.12 m^3 undergoes two processes. process 1-2: the air is compressed isothermally until the volume is halved. process 2-3: the air undergoes a constant pressure process until the volume is halved again. assume ideal gas behavior. a) determine the mass of the air, in kg. b) the work and the heat transfer for each of the two processes, in kj. (100 kj = 1 bar . m^3)