how to find radius of the circular motion?

A stone of mass 0.48 kg is attached to an extremely light thread, whose mass can be considered negligible, and swung around a fixed vertical axis Y so that the stone undergoes circular motion in a horizontal plane. The length of thread from the stone to the axis of rotation Y is L = 2.4 m and the thread makes an angle of θ = 71.0 ° to the vertical.