A restaurant kitchen has two food mixers, A and B. The number of times per week that A breaks down has a Poisson distribution with mean 0.4, while independently the number of times that B breaks down in a week has a Poisson distribution with mean 0,1. Find, to three decimal places, the probability that in the next three weeks

(a) A will not break down at all,

(b) each mixer will break down exactly once,

(c) there will be a total of two breakdowns. (L)