Question 148101
a) A ∩ B means what is in both A and B. {3} is in both
b) A ∩ C means what is both A and C.  Again only {3} is in both
c) A U C means what is in either A or C. {1 2 3 5 7}
d) B U C means what is in either B or C {3 4 5 6 7}
e) (A U B) ∩ C means what is in either A or B and also in C 
AUB = {1 2 3 4 5 6} what is also in C? {3 5}
f) A U (B U C) what is in any of the three {1 2 3 4  5 6 7}
g) (A ∩ B) ∩ C what is in each of the three {3}
h) (A ∩ B) U C  look at answer a above. Now what either in that or in C? {3 5 7}

does this help any?