A box sits on a flat board. You lift one end of the board, making an angle with the floor. As you increase the angle, the box eventually begins to slide down. You weigh the box and find that it has a mass of 2.42 kg and the angle at which it begins to slide is consistently 36 degrees. What is the coefficient of static friction? Be sure to show the algebraic form of all equations applied and report numerical answers with correct units and number of significant figures.