Which statement is true for a cooling curve? a. it shows how the temperature of the substance falls as heat is removed. b. it shows how the temperature of the substance changes when heat is applied. c. it shows the increase in the average kinetic energy of the particles. d. it shows how heat absorption affects the motion of particles. e. it shows how energy gain causes the temperature to fall.

How is electrolysis most commonly used to produce an energy source? a - splitting water molecules produces oxygen, which organisms breathe to fuel their bodies. b - splitting water molecules produces hydrogen gas, which is used to power machines through hydrogen fuel cells. c - splitting carbon dioxide molecules produces coal, a form of carbon that can be burned to produce heat. d - splitting carbon dioxide molecules produces natural gas, which can be burned to generate electricity in power plants.