It is claimed that 15% of the ducks in a particular region have patent schistosome infection. Suppose that seven ducks are selected at random. Let X equal the number of ducks that are infected.
(a) Assuming independence, how is X distributed?
(b) Find (i) P(X ≥ 2), (ii) P(X = 1), and (iii) P(X ≤ 3).