Easy Physics Questions, but can't figure out what I'm doing wrong.?

Question

1. A centrifuge rotator has a moment of inertia of 0.0315 kgm^2. How much energy is required to bring it from rest to 8000 rpm?

2. A merry-go-round has a mass of 1640 kg and a radius of 8.2 m. How much net work is required to accelerate it from rest to a rotation rate of one revolution rate of one reveolution in 8.00 s?

First correct answer will get best answer.

Answer 1

1 energy = I w^2 where w= angular velocity measured in radians/sec
2 work =change in kenetic energy