Chapter 2 - Set Theory - 2.4 Set Operations and Venn Diagrams with Three Sets - Exercise Set 2.4 - Page 92: 41

(A∩B∩C)= {6}

The set (A∩B∩C), represents the all the common elements of the universal set A and B and C. From the given Venn diagram we can conclude that the region V is common to the sets A & B & C. The element of these region is 6. So, (A∩B∩C)= {6}