The combined gas law states that
PV
T
= C, where P, V, and T are the pressure, volume, and temperature of a gas, and C are a constant.

Avogadro's Law says that the constant C is directly proportional to the amount of gas, n (moles), where the proportionality factor R is the universal gas constant. So, C = nR.

From these two laws, we can derive the Ideal Gas Law, which is

a p=VnRT
b PV=nRT
c P=v/nRT
d PV=nR/T

a. energy is absorbed in the reaction.

if in a given reaction the energy of products is greater than the energy of reactants it means that reaction is endothermic and during the reaction, the energy is absorbed by reactants. in an endothermic reaction, the products have more stored chemical energy than the reactants. and in this reaction the reactants are more stable than products before the compounds with less energy are always more stable.

the answers are

c and c