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An electric winch is used to raise a 40-kg package and a 10-kg package vertically up the side of a building as pictured in the diagram. There is a frictional force of 60 N acting between the wall and the 40-kg package.The angle the cable makes to the vertical is 15 degree.

(a) Calculate the force the winch must exert on the cable to slide the packages at a constant speed up the wall.
(b) If the packages are lowered with an acceleration 1.0 m/s 2 , what is the tension in the cable connecting the two packages?
(c) If the packages are raised with an acceleration of 1.0 m/s 2 , what is the tension in the rope connecting the two packages?