[填空题]
A rotating merry-go-round ma+os9+4gys 4zlv lf; zakes one complete (+spdts h46vn 27hf79 dozxijrevolution in 4.0 s (Fig. 8–38). (a) What is the linear speed of a cfsn(d6d svij+h4xzh729t p7 ohild seated 1.2 m from the center? $m/s$ (b) What is her acceleration (give components)? $m/s^2$ the center