Question 1 (6 marks) a) If a share of the PLM company earned a rate of return of 15% in 2020 and a rate of return of -8% in 2021. Calculate the average annual rate of return of PLM over this 2-year period (to percentages to 2 decimal places (e.g., 3.75%). b) If A share of EJM gained 19% in 2021 and a share of MNM lost 8.7% in 2021. Calculate the average rate of return of these 2 shares (to percentages to 2 decimal places (e.g., 3.75%). c) If an investor with an investment of $20,000 in the ABC corporation earned 18% return in 2019 and earned a rate of return of 10% in 2019 with an investment of $30,000 in the XYZ corporation, calculate this investor's average rate of return of her two-company investment (to percentages to 2 decimal places (e.g., 3.75%)