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The random variable X has probability density function: f (x ) = 10 [C - 2x OSx51 otherwise 1) What is the value of C? A) 1 B ) 2 C) 3 D) 4 E) 5 2) What is E[X]? A) 0 B) 1/2 C) 1/3 D) 2/3 E) None of the above. 3) What is the third quartile of X? A) 1/2 B) 5/8 C) 3/4 D) 3/2 E) None of the above