Answer:
I deeply believe that it would be options 1, 2, and 4? Sorry if i'm wrong and good luck!
This is just addition. Put 2140.56 on top, line up 9.3456 under it appropriately. Doing this will give you the answer: 2149.9056
The amount of energy required to change the temperature or phase of a reactant
CnH2n since the equivalent unsaturation is equal with 1