$($Problem $16\mathrm{.}38$ in Book$)$ The rod assembly is supported by ball$-$and$-$socket joints at A and $B.$ At the instant shown it is rotating about the $y$ axis with an angular velocity $=5ra\frac{d}{s^2}.$ Determine the magnitudes of the velocity and acceleration of point $C$ at this instant. Solve the problem using Cartesian vectors and equations vec$(V)=$vec$()$vec$(r{)}_P$ and vec$(a)=$vec$()$vec$(r{)}_P+$vec$()((vec())$vec$(r{)}_P).$