The air in a room has a mass of 50 kg and a specific heat of 1,000 J/(kg.°C). What is the change in thermal energy of the air when it warms from 20°C to 30°C?

A14 kg rock starting from rest free falls through a distance of 5.0 m with no air resistance. find the momentum change of the rock caused by its fall and the resulting change in the magnitude of earths velocity. earth mass is 6.0 * 10^24 kg. show your work assuming the rock earth system is closed.