Write the sets resulting from the following set concatenations.

Use the dot-dot form for infinite sets. To use the dot-dot form:

List as many members as needed to show the pattern of the strings and end with . . .}.

(a) {la, lala} {2, 22, 222}

(b) {la, lala} {a, aa, aaa, . . .}

(c) {a, aa, aaa, . . .} {h, rgh}

(d) {w} {o, oo, ooo, . . .} {f}