Gabrielle and Pierre are trying to move a 52 kg box by pushing it across the floor. Gabrielle is pushing with a force of 40 N [east], while Pierre is pushing with a force of 32 N [west]. There is also a friction force of 3 N [west] on the box. Assume the box travels 4 m [east].

Calculate the net force in the vertical direction on the box. In which direction is the net vertical force?