1. U = universal set are all the elements inside the rectangle U = {1,2,3,4,5,6,7,8,9,10,11,12,13,14,15) 2.AUB=A union B are all the elements inside circle A and all the elements inside circle B. AUB={1,2,4,5,6,8,9,10,12,14,15) 3. B O C = B intersect C are the elements common to both B and C. BC={1,14} 4. C'=C complement are all the elements of the universal set except those that can be found inside circle C. C'= {2,4,5,6,7,9,10,12,13} 5.A-C = A minus C is the set of elements which belongs to A but which do not belongs to C. A-C= {4,5,9,12}​