At a time t $=3\mathrm{.}00$ s$,$ a point on the rim of a wheel with a radius of $0\mathrm{.}250$ m has a tangential speed of $51\mathrm{.}0$ m$/$s as the wheel slows down with a tangential acceleration of constant magnitude $10\mathrm{.}0$ m$/$s$2.$

Calculate the angular velocity at t$=0.$

Calculate the wheel's constant angular acceleration.