Block A of mass 2m hangs from a cord that passes over a pulley and is connected to block B of mass 3m. Block B is free to move on a frictionless horizontal surface. The pulley is a disk with frictionless bearings, having radius R and moment of inertia 3MR^2. Block C of mass 4m is on top of block B. The surface between blocks B and C is not frictionless. shortly after the system is released from rest, block A moves with a downward acceleration a, and the two blocks on the table move relative to each other. a.) In terms of the given quantities and g, find the tensions, T1 and T2 for each section of string. For this I have the Sum of Fy= 2m(g-a)=T1 for Fx= T2= 7ma which the anwer given is different. The t1 is correct! But is this a typo or am I wrong? b.) If a=2m/s^2, determine the kinetic coefficient of friction between blocks B and C. I was thinking the force of friction would be equal to the tension in the x direction but when I work that out I dont get the right answer. Is that the right concept? c.) What is the acceleration of block C at this time? I dont have any work for this part yet but I'll put it on here just in case.