Canadians who visit the United States often buy liquor and

cigarettes, which are much cheaper in the United States. However,

there are limitations. Canadians visiting in the United

States for more than 2 days are allowed to bring into Canada one

bottle of liquor and one carton of cigarettes. A Canada Customs

agent has produced the following joint probability distribution

of the number of bottles of liquor and the number of cartons of

cigarettes imported by Canadians who have visited the United

States for 2 or more days.

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