Questions (a) and (b) require the formula for cumulative probability for a geometric distribution. See Geometric distribution - Wikipedia, the free encyclopedia:

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(a) Substitute p = 0.1 and k = 10.

(b) . Calculate each of these just like (a) but use p = 0.2.

(c) Poisson distribution with a mean of 5: . You need to substitute into the probability mass function (pmf). See Poisson distribution - Wikipedia, the free encyclopedia:

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Substitute and k = 0. Then do the same for k = 1, 2, 3, 4, 5. Then add up all these probabilities to get the answer.