An 8.0-kg stone at the end of a steel wire

An 8.0-kg stone at the end of a steel wire is being whirled in a circle at a constant tangential speed of 12 m/s. The stone is moving on the surface of a frictionless horizontal table. The wire is 4.0 m long and has a radius of 1.0 × 10-3 m. Find the strain in the wire.