Question):- In the figure given below, a force F parallel to the slope and having a magnitude of 20 N pushes a block of mass 3 kg with a constant speed.  If the initial and final positions of the block are P and Q, respectively, then calculate
(i) the work done by the force in moving the block from P to Q
(ii) the change in potential energy of the block
(iii) the amount of energy lost due to friction
(Take g = 10 m/s²)