While helping a friend move between apartments, you notice that a box loaded into the moving truck starts to slide backwards in the truck if the truck accelerates forward too rapidly. You also notice that the truck can be stationary on inclines of up to 22 degrees before the box starts sliding. What is the maximum acceleration that the truck can have on a level road without the box sliding? For full credit, include free-body diagrams showing the relevant forces in your Describe section. (Hint: what force keeps the box moving along with the truck when it accelerates?) Please help me solve this