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2. For any set S, denote by S the complement S of the set S. For any two sets S and T, denote by ST the intersection ST between the two sets. Example: The intersection ABCD is denoted by ABCD. Below is a Venn Diagram for some sets A,B,C, and D in which the 10 existing zones are marked. The zones that do not appear in the diagram are all the zones that require showing an intersection between the set D with either the set B or with the set C. The six such zones are: ABCDABCDABCDABCDABCDABCD Note that none of these zones contains D the complement of D and that none of them contains BC the intersection of the complements of B and C