Box A weighs 80 N and rests on a table. A rope that connects boxes A and B drapes over a pulley so that box B hangs above the table, as shown in the gure. The pulley and rope are massless, and the pulley is frictionless. What force n1 does the table exert on box A if box B weighs 35 N? Assume that the positive direction is upwards. What force n2 does the table exert on box A if box B weighs 70 N? Assume that the positive direction is upwards. What force 713 does the table exert on box A if box B weighs 90 N? Assume that the positive direction is upwards