A discus thrower is spinning the discus along a circular path in preparation for the throw. At one instant, the discus thrower?s angular velocity is 5.5 rad/s and .5 s later, the angular velocity of the thrower than increased to 12.7 rad/s
If the discus is held at 112 cm away from the thrower?s axis of rotation during the entire movement, what is the tangential velocity of the discus at the second instant?

Just use:

v = r\omega

omega is the angular speed, r is the radius from the centre.