A turntable wheel with radius $20$ centimeters and mass $2$ KG is spinning at a rate of $50$ revolutions per second when the power to the turntable is turned off the turntable wheel slows with constant angular acceleration and takes $80$ seconds to come to rest.

a$)$ what is the angular acceleration of the turntable as it comes to rest

b$)$ how many revolutions did the wheel make during this time it was coming to rest

c$)$ assuming the turntable as a solid disc find the torque of the turntable which made it stop eventually

d$)$ if a penny is placed at the edge of the turntable when it starts rotating find the linear$/$tangentinal velocity of the penny