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Question 4 I bet $100 on a horse A and $100 on horse B in separate races. On each horse, my expected dollar payoff (the money I expect to get back) is $60, and the standard deviation of my dollar payoff is $20. The two bets have no covariance. What is my expected total payoff? What is the standard deviation of my total payoff? (Hint: Suppose your dollar payoff on the first horse is a random variable X, and your dollar payoff on the second horse is Y. You know some rules about expected values and variances.)