Can somebody answer #5 to #9 for me

In a sample of oxygen gas at room temperature, the average kinetic energy of all the balls stays constant. which postulate of kinetic molecular theory best explains how this is possible?

All motion is caused by force? true or false

Given the following at 25c calculate delta hf for hcn (g) at 25c. 2nh3 (g) +3o2 (g) + 2ch4 (g) > 2hcn (g) + 6h2o (g) delta h rxn= -870.8 kj. delta hf=-80.3 kj/mol for nh3 (g), -74.6 kj/mol for ch4, and -241.8 kj/mol for h2o (g)