Random variable X has mean μX = 24 and standard deviation σX = 6.   Random variable Y has mean μY = 14 and standard deviation σY = 4.   A new random variable Z was formed, where Z = X + Y.  What can we conclude about X, Y, and Z with certainty?  That is, which one is true? Select one: a. μZ = 38            σZ = 6                          X and Y are related b. μZ = 38            σZ = 10

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