Q.6 - 10 are based on the followingbar graph. Jack has a collection of books of different subjects. Heprepared the above bar graph using these books. Jack wants to increase the number of books in his collection. He wants length of the bar of Physics books be equal to the length of Math books. How many Physics books you think Jack should buy?

• A. 8cm
• B. 16cm                      
• C. 32cm
• D. 64cm                      
• E. None of these