A Nuclear reactor produces product 20kg of uranium-235.if the half life is about 70years , how long will it take to decay to 0.1kg

The reaction below shows a system in equilibrium. how would a decrease in temperature affect this reaction? a. the rate of formation of the gases would increase. b. the equilibrium of the reaction would shift to the left. c. the equilibrium would shift to cause the gases to sublime into solids. d. the chemicals on the left would quickly form the chemical on the right.