A 3.50 kg book slides along a rough horizontal surface. Initially the book is traveling at 2.25 m/s. At some later point, the book is traveling at 0.18 m/s. What is the work done by the friction on the book

The scalar triple product computes the magnitude m of the moment of a force vector f about a specified line. it is m = (r × f) · n, where r is the position vector from the line to the point of application of the force and n is a unit vector in the direction of the line. use matlab to compute the magnitude m for the case where f = [12, −5, 4] n, r = [−3, 5, 2] m, and n = [6, 5, −7].