[填空题]
Starting from rest in thkh ga3a 2tds7lf)i8xfc,+/ bee pit arer;yq ap94gky ev8/b/2 mk w:hip ttq-5a, a race car accelerates at a uniform rate to a speed of 45 m/s in 15 s, moving on a circular track of radius 500 m. (only -tm2a48/kptq y;bhi 9wgprqv/ :yke 5fill in numerical value in the blanks)
(a) Calculate the tangential acceleration. $m/s^2$
(b) Calculate the radial acceleration when the instantaneous speed is equal to 30 m/s. $m/s^2$
