A 5.45-kg ball hangs from the top of a vertical pole by a 2.19-m-long string. The ball is struck, causing it to revolve around the pole at a speed of 4.37 m/s in a horizontal circle with the string remaining taut. Calculate the angle, between 0° and 90°, that the string makes with the pole. Take g = 9.81 m/s2.