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3. A spinner from a board game randomly indicates a real number between 0 and 10. The spinner is fair in the sense that it indicates a number in a given interval with the same probability as it indicates a number in any other interval of the same length. (a) (5 points) Explain why the function f (:17) is a probability density function for the spinner's value. 0.1 ifgmgl it): . 0 1f$10 (b) (5 points) What do you think the value of the mean is? Check your guess by eval- uating the integral