Three and four hundredths means the same as... A: .34 B: 3.004 C: 3.04 D: 3.4 E: none of these

How do you solve a question like this?

Let f(x) = 3 − x . find the average rate of change of f(x) from x = a to x = a + h and simplify your answer so that no single factor of h is left in the denominator.

The volume of a cube-shaped shipping container is 13,824 cubic inches. find the edge length of the shipping container.