The figure shows a system consisting of three blocks, a light frictionless pulley, and light connecting ropes that act horizontally on the upper two blocks. Block A sits on top of block B. Block A has a mass of 10.0 kg and is connected to the left wall so that it remains motionless. Block B has a mass of 9.0 kg and is on a perfectly smooth horizontal table. The coefficient of kinetic friction between blocks A and B is _k = 0.30. Block C hangs from a light rope connected to block B on the table. The mass of block C is set so that it descends at a constant velocity of 3.25 m/s.

A B C