A. the carbons are unbalanced
B. the hydrogens are unbalanced.
D. the chlorines are unbalanced.
That leaves C. to be correctly balanced.
You just multiply these two numbers, it's 1250J
Meters per second squared:

If you think about it, acceleration is about how fast speed changes. Speed is measured in meters per second:

So if you take that and just measure it over time, you get meters per second squared.
Earth is the center according to the geocentric model.
Answer:
If efficiency is .22 then W = .22 * Q where Q is the heat input
Heat Input Q = 2510 / .22 = 11,400 J
Heat rejected = 11.400 - 2510 = 8900 J of heat wasted
Also, 8900 J / (4.19 J / cal) = 2120 cal