(a) 3 situations where work is done are:
(i) If a pebble lying on a surface is pushed, the pebble moves through a distance. In this situation work is said to be done.
(ii) If a girl pulls a trolley and the trolley moves through a distance. In this situation work is done.
(iii) If a book is lifted to a height, the force is applied and the book rises up, work is said to be done.
