A. 20. Which is the best description of activation energy? (HB2A2)
Energy added to start a reaction.
b. Energy released as the reaction proceeds
C. Energy stored within the reactant molecules.
d. Energy stored within the product molecules.

c is the answer to this question. altitude affects the weather because air molecules evaporate.

the earth is thought to have been formed about 4.6 billion years ago by collisions from a cloud of hydrogen, helium, rock, ice and other materials. these were pulled together by gravity to form objects in and around earth like- asteroids and small early planets called planetesimals.

so, the best possible answer to this question will be option d- to harden materials to form different parts of earth’s layers