I need help on this one too I think it might be (b)
Combustion is a chemical reaction between a fuel and an oxidant, oxygen, to give off combustion products and heat. Complete combustion results when all of the fuel is consumed to form carbon dioxide and water, as in the case of a hydrocarbon fuel. Incomplete combustion results when insufficient oxygen reacts with the fuel, forming soot and carbon monoxide.
The complete combustion of propane proceeds through the following reaction:

+

-->

+

Combustion is an exothermic reaction, which means that it gives off heat as the reaction proceeds. For the complete combustion of propane, the heat of combustion is (-)2220 kJ/mole, where the minus sign indicates that the reaction is exothermic.
The molar mass of propane is 44.1 grams/mole. Using this value, the number of moles propane to be burned can be determined from the mass of propane given. Afterwards, this number of moles is multiplied by the heat of combustion to give the total heat produced from the reaction of the given mass of propane.
14.50 kg propane x <u> 1000 g </u> x <u> 1 mole propane </u> x <u> 2220 kJ </u>
1 kg 44.1 g 1 mole
=
729,931.97 kJ
Answer:
The amount is 
Explanation:
From the question we are told that
The distance traveled per day is 
The cost of one liter is 
The car's gas mileage is 
Generally the amount of distance covered in one week is evaluated as


The amount of gas used in one week by the car is mathematically represented as

=> 
=> 
converting to liters

Thus the amount spent on gas in one week is

=> 
=> 
I think is 6.588579795x10^13 Kg because the equation is E=mc^2 and E is your Joules and c^2= 9x10^16 so m=(c^2)/E