A \(0.20-\mathrm{kg}\) turntable of radius \(0.20 \mathrm{~m}\) spins about a vertical axis through its center. A constant rotational acceleration causes the turntable to accelerate from 0 to 28 revolutions per second in \(8.0 \mathrm{~s}\). Calculate

(a) the rotational acceleration and 

\((b)\) the torque required to cause this acceleration.