Please be as descriptive as possible so I can understand it better.

4. Suppose that the rates of return for assets A, B, C, and D all have standard deviations of 10%, but are uncorrelated with each other (i.e. . PAB = 0, pc:0, pAD:0, etc.) a. Calculate the standard deviation of the rate of return for a portfolio consisting of 1/2 asset b. Calculate the standard deviation of the rate of return for a portfolio consisting of 1/3 asset c. Calculate the standard deviation of the rate of return for a portfolio consisting of 1/4 asset d. What happens to the portfolio's s riskiness as the number of assets included in it increases? A and 1/2 asset B. A, 1/3 asset B, and 1/3 asset C. A, 1/4 asset B, 1/4 asset C, and 1/4 asset D