[填空题]
A rotating merry-go-round makes one complete revolutionge cqbmyh )+g2)1q) uj in 4.0 s y wl(ctej** 6p. jp;at(Fig. 8–38). (a) What is the linear speed of a child seatt wc( j*. e6;ypljp*ated 1.2 m from the center? $m/s$ (b) What is her acceleration (give components)? $m/s^2$ the center