[填空题]
A cooling fan is turned ofv0pm bq l dl0*y b,tou;/f-ya*f when it is running at 850rev/min It turns 1w bm6 ry6s:3guz8:6nz;re g.gf qcpp;500 revolutions before ise g 6g:g6p8fwpcb:q.z 6zr; 3nu;rymt comes to a stop. (a) What was the fan’s angular acceleration, assumed constant? $\frac{rad}{s^2}$ (b) How long did it take the fan to come to a complete stop? s