HEEELLLPPP

Let S be the universal set, where:S = {1, 2, 3, ..., 18, 19, 20}
Let sets A and B be subsets of S, where:

Set A = {4, 6, 8, 15, 16, 17, 18, 19, 20}

Set B = {1, 2, 4, 6, 7, 11, 17, 18}

Find the following:

LIST the elements in the set (AUB):
(AUB) = {

Enter the elements as a list, separated by commas.

LIST the elements in the set (A n B):
(An B) = {

Enter the elements as a list, separated by commas.