An airplane propeller is rotating at 1250rpm .
a) Compute the propeller's angular velocity in rad/s.
b) How many seconds does it take for the propeller to turn through 45.0 degrees?
c) If the propeller were turning at 18.0rad/s , at how many rpm would it be turning?
d) When the propeller were turning at 18.0rad/s , what is the period (in seconds) of this propeller?