What is the magnitude of the center-of-mass acceleration for the wheel assuming it rolls without slipping down the ramp (in terms of M, g, I, and R)?

A wheel of moment of inertia I, mass M, and radius R is placed on a ramp tiled at an angle theta from the horizontal.  The wheel is released from rest.  What is the magnitude of the center-of-mass acceleration for the wheel assuming it rolls without slipping down the ramp (in terms of M, g, I, and R)?