please explain this question. how can i solve this question? (which number should i use it for?)

You inform your boss of these findings and she is happy with the addition of the extra four counties to the portfolio and the reduction in risk. However, she informs you that the 9% returning portfolio you have constructed is not as 'efficient' as it might be as you have forgotten all about the risk-free asset... oops! You quickly do some research and determine that the appropriate risk-free rate to use is 0.25% per annum. Perform the following tasks to adjust your portfolio weights: 3. (a) Construct and plot the MVS (with short sales allowed) for the eleven country indices plus the risk-free asset paying 0.25% . (b) Identify the tangency portfolio, i.e. report its portfolio weights, expected return, and standard deviation of returns. Furthermore, illustrate its tangency property graphically by plotting the MVS from 2.(c) on the same set of axes. (c) Determine and report the new portfolio weights for the efficient portfolio with 9% expected return. (d) Calculate and report the reduction in risk of the 9% returning efficient portfolio that can be achieved by adding the risk-free asset to the portfolio of eleven risky assets