Suppose that 10% of the clerical staff in an office smoke cigarettes. Research shows that 60% of smokers and 15% of nonsmokers suffer a breathing illness by age 65. (a) Do these percentages indicate...

Suppose that 10% of the clerical staff in an office smoke cigarettes. Research shows that 60% of smokers and 15% of nonsmokers suffer a breathing illness by age 65.

(a) Do these percentages indicate that smoking and this breathing illness are independent?

(b) What’s the probability that a randomly selected 65-year-old employee who has this breathing illness smokes?