[填空题]
The tires of a car ma(r 4p;w81nxuec,t tspke 650 xy)dok y*:.cker nkisja2/7 revolutions as the car reduces its speed uniformly from 95km/h to 45km/h The tires h0e7j:. y/ky2 nsicd*ok kx)raave a diameter of 0.80 m. (a) What was the angular acceleration of the tires? $\approx$ $rad/s^2$ (b) If the car continues to decelerate at this rate, how much more time is required for it to stop? s