The angular position of a point on the rim of a rotating wheel is given by θ = 4.0t - 3.0t² + t³, where θ is in radians and t is in seconds. What are the angular velocities at

a) t = 2.0 s and

b) t = 4.0 s?

c) What is the average angular acceleration for the time interval that begins at t = 2.0 s and ends at t = 4.0 s? What are the instantaneous angular accelerations at

d) the beginning and

e) the end of this time interval?