Tamika is pushing a 30 kg heavy box horizontally on a level floor. Unfortunately, the box does not move. Assume Tamika's push is 150 N.2. Xiao joins Tamika in pushing the heavy box in the same direction as before. This time around the box is seen to speed up at 2 m/s2. If the force of sliding friction between the box and the surface has a magnitude of 240 N, determine the total force exerted by both Xiao and Tamika on the box