A student is measuring the quality of industrial grease as it ages. To keep the measurement simple, the student uses an inclined board with a weighted down bin on top of it. The student greases up the surface, and tilts the board up to find the angle at which the bin slides. If the bin and its contents weigh 5.5kg, the board is 1.8m long, temperature in the room is 20.68 C, and the angle is found to be 29.76 to the horizontal, what is the coefficient of static friction during this run? (Answer's number of decimals : 2)