A block A of mass 4 kg rests on a rough incline that makes an angle of $37°$ with the horizontal ($\sin37°=0.6$, $\cos37°=0.8$). The coefficient of static friction between A and the incline is $0.5$. A light string over a frictionless pulley at the top of the incline connects A to a hanging block B of mass 2 kg, as shown. Take $g=10\ \text{m/s}^2$. If the system is released from rest, what is the magnitude of the acceleration of the blocks?

Fig. 1: A 4 kg block A on a rough 37 degree incline, joined by a string over a pulley at the top of the incline to a 2 kg block B hanging beside it.