The slider P can be moved inward using string S$.$ The angular position of the arm is given by $=0\mathrm{.}8$t $$ t$2/20$ where $$ is in radians and t is in seconds. At t $=0,$ r $=1\mathrm{.}6$ m$,$ and P is drawn inward at a constant rate of $0\mathrm{.}2$ m$/$s$.$ Find the magnitudes and directions of velocity and acceleration of P when t $=4$ s$.$