[填空题]
A rotating merry-go-round makes on(h7guk9x:i0sd u4 fhmzx tk5 )cf)bw(e complete revolution in 4.0 s (Fig. 8–38).a(wc wbxa445smw ; um7 (a) What is thmw74cw5;s u amwb(a 4xe linear speed of a child seated 1.2 m from the center? $m/s$ (b) What is her acceleration (give components)? $m/s^2$ the center