Of the fifty states, how many have mandatory safety belt laws?

I don't normally copy and paste answers in here... but I didn't want to give you false information. So here's this :)

With the exception of New Hampshire, all states and the District of Columbia require adult front-seat occupants to use seat belts. Adult rear-seat passengers also are covered by the laws in 31 states and the District of Columbia. Children are covered by separate laws.

what are the sentences? so we can answer the question.

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