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Question 3: Beta (4 marks) Assume that both Spark and Vodafone plot on the Security Market Line (SML). Spark has a beta of 2.6 and an expected return of 21.2%. Vodafone has a beta of 0.9 and an expected return of 9.3%. The expected return on the market portfolio is 12%, and the risk-free rate is 4%. SparkVodafone Market Portfolio Risk-free Asset 0.9 9.3% 1.0 120% 0.0 4.0% 2.6 Expected Return | 21.2% | a) If you wish to hold a portfolio consisting of Spark and Vodafone and have a portfolio beta equal to 1.5, what proportion of the portfolio must be in Spark? (2 marks) b) What is the expected return on this portfolio? (2 marks)