please help me to answer this question

Mr. Ali aged 65 years and Mr. Suliman aged 25 years comes to you for investment advice. Mr. Mohammed has OMR 50,000 and Mr. Javed has OMR 25,000. Investment alternatives available are as below: - Securities Return Probability Equity 15% ? Preference share 12% ? Government bonds 8% ? Debenture 13% ? Bank deposit 3.5% ? As an investment consultant you are required to advice both the investor in which securities to invest their surplus money and also find the Expected Return, Variance. Standard Deviation, Covariance and Coefficient of Variance their portfolio after one year and provide valuable information to Mohammed and Javeed Note: 1. You can make your own combination of the securities by using the above investment alternatives. 2. You can assume and use your own values for the probability