Answer number 4 please thank you.

Answer:
See below
Step-by-step explanation:
A) B intersection C = {6,12} <===== the elements common to both
B) B union C = { 2 3 4 6 8 9 10 12 ) <== all the elements from both
C ) { } { 6} { 12 } { 6,12} <===== Four