A 3.0-{rm kg} block sits on top of a 5.0-{rm kg} block which is on a horizontal surface. The 5.0-{rm kg} block is pulled to the right with a force vec F as shown in the figure . The coefficient of static friction between all surfaces is 0.61 and the kinetic coefficient is 0.37.
What is the minimum value of F needed to move the two blocks?