#### Answer

(a) {1, 2, 3, 4, 5, 6, 7, 8}
(b) {2, 4, 6}

#### Work Step by Step

a) To find the set of the union of A and B, first, we turn to what we know about unions: they are the set that consists of all elements that are in A or B (or in both). Thus:
A = {1, 2, 3, 4, 5, 6, 7}
B = {2, 4, 6, 8}
Union of two given sets is the smallest set which contains all the elements of both the sets. To find the union of two given sets A and B is a set which consists of all the elements of A and all the elements of B such that no element is repeated.
Thus, the union of A and B is: {1, 2, 3, 4, 5, 6, 7, 8}
b) An intersection of two sets contains all elements of A that also belong to B (or equivalently, all elements of B that also belong to A), but no other elements. Or, in other words, is made up of elements common to A and B.
Thus, the intersection of A and B is: {2, 4, 6}