Suppose a car dealer earns $1000 on each used car sold, and earns $2000 on each new car sold.

Suppose a car dealer earns $1000 on each used car sold, and earns $2000 on each new car sold. In a month, the number of used cars sold has a mean of 10 with a standard deviation of 5, and the number of new cars sold has a mean of 20, with a standard deviation of 8. Suppose the number of used cars sold, and the number of new cars sold are independent. Find the mean and standard deviation of the dealer's profit in a month. 

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