Seat belt use is the most effective way to save lives and reduce injuries in motor vehicle crashes. In a 2014 survey, respondents were asked, "How often do you use seat belts when you drive or ride in a car?". The following table shows the distribution of seat belt usage by sex.

(a) Calculate the marginal probability that a randomly chosen individual always wears seatbelts.

(b) What is the probability that a randomly chosen female always wears seatbelts?

(c) What is the conditional probability of a randomly chosen individual always wearing seatbelts, given that they are female?

(d) What is the conditional probability of a randomly chosen individual always wearing seatbelts, given that they are male?

(e) Calculate the probability that an individual who never wears seatbelts is male.

(f) Does gender seem independent of seat belt usage?

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Seat Belt Usage Always Nearly always Sometimes Seldom Never Total Male 146,018 19,492 7,614 3,145 4,719 180,988 Sex Female 229,246 16,695 5,549 1,815 2,675 255,980 Total 375,264 36,187 13,163 4,960 7,394 436,968