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9. Your portfolio is comprised of 40 percent of stock X, 20 percent of stock Y, and the rest in stock Z. Stock X has an expected return of 10%, stock Y has an expected return of 15%, and stock Z has an expected return of 2%. What is the expected return of your portfolio? 10. Your portfolio is comprised of 20% of stock X, 40% of stock Y, and the rest in stock Z. Stock X has an expected return of 12% and stock Y has an expected return of 20%. If the portfolio has an expected return of 18%, what is the expected return of stock Z