Only 30 of the people in a large city fed that its mass tran

Only 30% of the people in a large city fed that its mass transit system is adequate. If 20 different people are selected at random. Find the probability that at most five people will feel that the system is adequate Find the probability that exactly six will feel that the system is adequate. What is the expected number (i.e mean) in the sample who feel that muss transit is adequate? What is the standard deviation of the number out of 20 who feel that mass transit is adequate?

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