Two blocks are connected by a very light string passing over a massless and frictionless pulley (Fig. E6.7). Traveling at constant speed, the 20.0-N block moves 75.0 cm to the right and the 12.0-N block moves 75.0 CIJl downward. During this process, how much work is done (a) on the 12.0-N block by (i) gravity and (ii) the tension in the string') (b) On Ihe 2(l.()-N block by (i) gravity,(ii) the tension in the string. (iii) friction, and (iv) the normal force') (cl Find the total work done on each block.