Explanation:
The period is the time it takes for the spinner to rotate one revolution, or 2π radians.
T = 2π / ω
T = (2π rad) / (140 rad/s)
T = 0.0449 s
The tangential velocity is the product of the angular velocity and the radius.
v = ωr
v = (140 rad/s) (3.7 cm)
v = 518 cm/s