*I really don't know how to get started. I have done lots of the homework, but this one (and a couple of others) are really giving me PROBLEMS.*

Question

A large fish hangs from a spring balance supported fromthe roof of an elevator.

If the elevator has an upward acceleration of 2.65 m/s^2 and the balance reads 70.0 N, what is the true weight of the fish?
Answer should be expressed in N.

Under what circumstances will the balance read 34.0 N?
Answer should be expressed in m/s^2.

What will the balance read if the elevator cable breaks?
Answer should be expressed in N.