Roster form:
In this form, a set is defined by listing elements, separated by commas, within braces {}.
(i) {a, b, c, d}
(ii) {1, 2, 3, 4}
(iii) {11, 13, 17, 19}
(iv) {2, 4, 6, 8, 10,...}
(v)
(vi) {2, 3, 5}
(vii) {17, 26, 35, 44, 53, 62, 71, 80}
(viii) {T, R, I, G, O, N, M, E, Y}
(ix) {B, E, T, R}