A small block with a mass of 0. The block is originally revolving at a distance of 0.

A small block with a mass of 0.190 is attached to a cord passing through a hole in a frictionless, horizontal surface (the figure ). The block is originally revolving at a distance of 0.50 from the hole with a speed of 0.90 . The cord is then pulled from below, shortening the radius of the circle in which the block revolves to 0.15 . At this new distance, the speed of the block is observed to be 3.00 . How much work was done by the person who pulled on the cord?