Circles C, B, and P overlap. Circle C contains 9, circle B contains 11, and circle P contains 7. The overlap of circles C and P contains 6, the overlap of circles C and B contains 5, and the overlap of circles B and P contains 4. The overlap of all 3 circles contains 3.
Westside High’s 2015 senior-class science enrollment is summarized by the Venn diagram. Chemistry, biology, and physics class enrollments are denoted by the sets C, B, an P, respectively.

How many students are in the 2015 senior class?

How many students are taking chemistry and biology, but not physics?

How many students are not taking science