Probability distribution for discrete random variables

A health insurance policy covers visits to a doctor's office. Each visit costs 100. The annual deductible on the policy is 350. For a policy, the number of visits per year has the following probability distribution:

A policy is selected at random from those where costs exceed the deductible.


a. Calculate the probability that this policyholder had exactly five office visits.

b. Calculate the probability that this policyholder had at least five office visits.

c. Calculate the probability that this policyholder had at most five office visits.

d. Calculate the probability that this policyholder had no office visits.

e. Calculate the probability that this policyholder had four or six office visits.