How many nonzero entries does the matrix representing the relation R onA = {1, 2, 3, .

Question:

How many nonzero entries does the matrix representing the relation R onA = {1, 2, 3, . . . , 100} consisting of the first 100 positive integers have if R is
a) {(a, b) | a > b}?
b) {(a, b) | a ≠ b}?
c) {(a, b) | a = b + 1}?
d) {(a, b) | a = 1}?
e) {(a, b) | ab = 1}?