I was wondering how I could find the mass function and expected value for this problem?

The number NV of eggs that are laid by a denizen of the deep is governed by a geometric distribution with parameter o. Writing B = 1 - o, its mass function is given by P{N = n} = w(n; a) := Bra (n20). The survival of the eggs is governed by a Bernoulli process, each egg surviving, independently of the others, with probability p. Let K denote the number of survivors. (a) Determine the mass function of K, that is to say, evaluate the two-parameter function P{K = k} = g(k) = g(k; a, p) (k >0). (b) Thence evaluate E(K). [Hints: For (a), the identity ark E k (1 - x)k+1 (12)