[填空题]
A grinding wheel is a uniform9s-a5 sp xiiwhy 2),ye cylinder with a radius of 8.50 cm and a mass of 01xh3p-ek+ aasdt gk23 .580 kg. Calculat31a hd2ka3g-k e+pxtse (a) its moment of inertia about its center, $\approx$ $kg \cdot m^2$ (b) the applied torque needed to accelerate it from rest to 1500 rpm in 5.00 s if it is known to slow down from 1500 rpm to rest in 55.0 s。 $m \cdot N$