A wheel with a tire mounted on it rotates at the constant rate of 2.51 times a second. A tack is stuck in the tire at distance 31.3 cm from the...

A wheel with a tire mounted on it rotates at the constant rate of 2.51 times a second. A tack is stuck in the tire at distance 31.3 cm from the rotation axis. Noting that for every rotation the tack travels one circumference, find the tack's tangential speed. What is the tack's radial acceleration?