[问答题]
A turntable of radiuji ;we / -b3;cvjujvw*sln4(n o z3 f-cc ny4tze;vhj88 i:xd;r $R_1$ 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, $\omega_1$ / $\omega_2$