To answer this item, we use dimensional analysis and conversion factor, 1 revolution is equal to 2π rad. Using the concept and the given,
n = (14.2 revolutions / 8 seconds)(2π rad/1 rev)
n = 11.15 rad/s
Thus, the angular velocity is equal to 11.15 rad/s.
The answer is probably the first or second one. I made it easier for you
