Two blocks sit on a horizontal surface. They are connected to each other by a massless cord. The block on the left has a mass of 5.1 kg and the block on the right has a mass of 3.0 kg. Another massless cord is attached to the block on the right and pulls that block with a horizontal force of 48 N causing both blocks to accelerate at a rate of 1.6 m/s2 to the right. The block on the right has a frictional force of 12 N opposing the motion.
a) What is the frictional force opposing the motion for the block on the left?
b) What is the tension in the cord connecting the two blocks?