A hockey puck of mass m = 150 g is attached to a string that passes through a hole in the center of a table, as shown in the figure below. The hockey puck moves in a circle of radius r = 0.95 m. Tied to the other end of the string, and hanging vertically beneath the table, is a mass M = 0.90 kg. Assuming the tabletop is perfectly smooth, what speed must the hockey puck have if the mass M is to remain at rest?