Answer
(a) $\theta = 46~rev/min^2$
(b) $\omega = 46~rpm$
Work Step by Step
(a) $\theta = \frac{1}{2}\alpha t^2$
$\alpha = \frac{2\theta}{t^2} = \frac{(2)(23~rev)}{(1.0~min)^2} = 46~rev/min^2$
(b) $\omega = \alpha t = (46~rev/min^2)(1.0~min) = 46~rpm$