The green block(B) has a mass of 7.00 kg and is moving to the left at a speed of 2.60m/s. The red block (A) has a mass of 6.00kg and is moving to the right. The two blocks undergo a perfectly inelastic collision. What should the velocity of the red block be in order to have the two blocks move to the left with a speed of 0.56 after the collision?