In my tenth-grade-level physical science class, we're studying heat, and I completely don't get it. I'll read the definition for specific heat over and over, and I still don't understand it. "For all substances, specific heat is a characteristic physical property, which is denoted by c. In this book, we will think of specific heat of any substance as the amount of energy required to raise 1 kg of that substance by 1 K." Or: "The quantity of heat required to raise a unit mass of homogenous material 1 K of 1(degree)C in a specified way given constant pressure and volume." Huh?!?

Question

I don't get anything in this chapter.
We were assigned fifteen problems the other night, seven of which I got wrong (a friend helped me on all of them, and though I sort of got it while she was guiding me through it, it's still going over my head). Problem one states:
A 250 g sample of water with an initial temperature of 98.8(degrees)C loses 7500 joules of heat. What is the final temperature of the water? (Remember, final temp = initial temp - change in temp)
It's given in the book that the specific heat of water is 4186 J/g x (degrees) C.
How do I figure that?
Or... this?
2. Coper has a specific heat of 0.38452 J/g x (degrees) C. How much change in temperature would the addition of 35,000 joules of heat have on a 538.0 gram sample of copper?

All the other questions are basically like that, but I just don't get it. This is the equation we've been given:
Energy (Q) = specific heat (c) x mass (m) x temperature change ((delta) T)
Q = cm(delta)T.
Again, I totally don't understand it.