[填空题]
A rotating merry-go-roun z(toyev(*whd/.p*.on zmt+hd makes ns 6-dvcub3z b1oqy:4one complete revolution in 4.0 s (Fig. 8–38). (a) What is the linear speed of 143vdo-bc: qbunzsy 6a child seated 1.2 m from the center? $m/s$ (b) What is her acceleration (give components)? $m/s^2$ the center