Given the Following Data, Calculate the Heat of Reaction (Combustion)

Given the following data, calculate the heat of reaction (combustion) for one gram of butane, C₄H₁₀. Report your result in kJ/g.
Standard heats of formation (kJ/mole) :
H₂O(g) : -241.82
CO₂(g) : -393.5
Butane: -147.6
Formula weight of butane: 58.12 g/mole
L/mole of a gas at STP: 22.4L

A) -45
B) 18
C) -91
D) -73
E) none of the above