If 1.00 kilograms of coal is burned, approximately 3.00 x 107 joules (j) of energy is released. how many tons of coal, when burned, would produce approximately 9.00 x 1016 j?

Explanation:

We can resolve this problem using a proportion because the ratio tons burned and energy produced is constant, using x for tons burned of coal to produce :

solving the proportion:

Now we have the answer but in kilograms we should convert this knowing that 1 ton = 1000 kg:

there are no contact forces mentioned on the list of choices that you've provided.