Two masses m1 and m2 are connected by a light string that passes over a pulley of radius R and rotational inertia I. The string does not slip on the pulley, and friction in the axle is negligible. If m1>m2, which of the following gives the magnitude a of the linear acceleration of the masses immediately after release?
a) a=m1+m2+I/R2(m1+m2)g
b) a=m1+m2+I/R2(m1−m2)g
c) a=m1+m2(m1−m2)g
d) a=m1+m2−I/R2(m1−m2)g