According to the given bar graph,

(i) (a) In 1989, 180 books were sold. (b) In 1990, 475 books were sold. (c) In 1992, 225 books were sold.

(ii) In 1990, about 475 books were sold and in 1992, about 225 books were sold.

(iii) In 1989 and 1992 fewer than 250 books were sold.

(iv) By reading the graph, we calculate that 180 books were sold in 1989.