Luggage is transported from one location to another in an airport by a conveyor belt. At a certain location, the belt moves down an incline that makes an angle of.2.5o with the horizontal. Assume that with such a slight angle there is no slipping of the luggage. Determine the magnitude of the frictional force by the belt on a box weighing 69 N when the box is on the inclined portion of the belt and the belt speed is
(a) 0 and constant,
(b) 0.65 m/s and constant,
(c) 0.65 m/s and increasing at a rate of 0.20 m/s2,
(d) 0.65 m/s and decreasing at a rate of 0.20 m/s2, and
(e) 0.65 m/s and increasing at a rate of 0.57 m/s2
(f) For which of these five situations is the frictional force directed down the incline?