(a) Work done is zero. This is because equal and opposite work is done in the two paths.
(b) (i) Work done by me is positive and having a value = mgh. This is because I am applying force in vertically upward direction on the carton to hold it and displacement is also in the same direction.
(ii) Work done by the force of gravity on the carton = – mgh. This in because force is vertically downward but motion is vertically upward.
(b) Anil has greater power because his rate of doing work is more. Ashok has more energy as he worked for a longer time and the total work done by him in definitely more.