At the instant shown, the wheel rotates with an angular velocity of $=14\mathrm{.}4ra\frac{d}{s}$ and an angular acceleration of $=7\mathrm{.}2ra\frac{d}{s^2}.($Figure $1)$

Part A

Determine the angular acceleration of link $BC$ at the instant shown measured counterclockwise.

Express your answer in radians per second squared to three significant figures. Assume the positive direction is counterclockwise. $***$ANSWER IS NOT $1\mathrm{.}8$ rad$/$s$^2$