[问答题]
A turntable of radius *p9ba 0 5ihfksitelvrs7 bsw wv kyx tr y,b)y*x)y-,f34 (*h:$R_1$ is turned by a circular rubber roller of radius $R_2$ in contact with it at their outer edges. What is the ratio of their angular velocities, $\omega_1$ / $\omega_2$