The ratio of adult males to adult females living in a certain town is 17 :18, and 2/9 of these adults, independent of gender, do not have a driving license.

a. Show that the probability that a randomly selected adult in this town is male and has a driving license is equal to 17/45.

b. Find the probability that, in a randomly selected sample of 25 adults from this town, from 8 to 10 inclusive are females who have a driving license