PROBLEM $15\mathrm{.}235$

The $400-mm$ bar $AB$ is made to rotate at the rate ${}_2=d\frac{}{d}t$ with respect to the frame $CD$ which itself rotates at the rate ${}_1$ about the $Y$ axis. At the instant shown ${}_1=12ra\frac{d}{s},d\frac{{}_1}{d}t=-16ra\frac{d}{s^2}{}_2=8ra\frac{d}{s},d\frac{{}_2}{d}t=10ra\frac{d}{s^2},$ and $=60.$ Determine the velocity and acceleration of point $A$ at this instant.