I need help with this problem, please can you explain step by step

17. (15 points) A new medical test has been developed by a laboratory to test u virus. The research group claimed that if an individual is infected by the virus, the probability that the test result is positive is 0.95; if the individual is not infected, the probability that the test result is negative is 0.9. Suppose we know that the proportion of infection in the population is about 0.08. (a) (3 points) If 100 individuals are selected from the population, what is the average number got infected? (b) (5 points) What is the probability that the test result for an individual is positive? (c) (4 points) What is the probability that the individual gets infected indeed if the test result is positive? (d) (3 points) Comments on the new testing method based on your calculation results