At what temperature will the sphere begin to brush the floor ? T = ____ degrees C

A Foucault pendulum consists of a brass sphere with a diameter of 38 0 cm suspended from a steel cable 11 0 m long (both measurements made at 20.0 (). Due to a design oversight, the swinging sphere clears the floor by a distance of only 1 50 mm arn when the temperature is 20.0" C