rotational kinematics

1) A Frisbee thrown from rest achieves a rotational speed of 46.5 rad/s in 0.420 s. What is its angular acceleration?

2) If
a rotating disc has an acceleration of −0.85 rad/s^{2} and an
initial velocity of 22 rad/s, how many radians will it spin before coming to a
stop? How many rotations is that?

3) Another one of those spinning things has a speed of 35 rad/s. To make it stop in 5.4 s over 3.0 rotations, what acceleration will it experience?