[填空题]
The tires of a car mam9lp nhuc af1/nwhjx8i(s 4)5ke 6ntj0i7bfk0:qv6z;7 nx w/r1njkthe 85 revolutions as the car reduces its speed uniformly from 90km/h to 60km/h The tires have a dijvrq0twx;nhtzfn /i60: 76n7k1k be j ameter of 0.90 m. (a) What was the angular acceleration of each tire? $\approx$ $rad/s^2$(round to two decimal place) (b) If the car continues to decelerate at this rate, how much more time is required for it to stop? s