Problem $6$: A $3-$phase induction motor with $4$ poles is being driven at $60$ Hz and is running in its normal operating range. When connected to a certain load, the motor rotates at a speed of $1600$ rpm and outputs $850$ W$.$ a$)$ What is the slip and developed torque? $(5$ points$)$ b$)$ What is the new slip and motor speed if the developed torque is reduced to $4$ Nm$?(10$ points$)$