a) To determine which category represents approximately one-fifth of the publisher's revenue, you can compare the given pie chart with a pie chart divided into 5 parts.
The category that is approximately one-fifth of the revenue, that is, 20% of the total revenue, is textbooks.
To solve parts b and c you can use the following pie chart to compare with the given chart for the publisher's revenue:
b) Looking at the pie charts, the categories "paperback" and "poetry" are approximately 20% of the total revenue.
c) The category "Nonfiction" is 10% of the total revenue, the category "poetry" is approximately half of the size of the category "nonfiction" so you can say that it corresponds to 5% of the total revenue.