A block of mass 1.00 rm kg sits on an inclined plane as shown. (Intro 1 figure) A force of magnitude 70.0 rm N is pulling the block up the incline at constant speed. The coefficient of kinetic friction between the plane and the block is 0.500. The inclined plane makes an angle 30.0 degrees with the horizontal. What is the total work W_fric done on the block by the force of friction as the block moves a distance 8.00 rm m up the incline?