[填空题]
A rotating merry-go-rouc6i h/989l v(r9 +icplpfkgtxnljdvv,phpe m(z9y28 3d makes one complete revolution in 4.0 s (Fig. 8–38). (a) What is the linear speed of a child seated 1.2 m frvvzm38p (d yh9, eljp2om the center? $m/s$ (b) What is her acceleration (give components)? $m/s^2$ the center