this is from Pearson's financial

Question Help The following table contains monthly returns for Cola Co and Gas Co for 2010 (the retums are shown in decimal form, te 0035is 35%). Using this table and the fact that Cola Co. and Gas Co have a correlation of -0.0969. calculate the volatility (standard deviation) of a portfolio that is 60% invested in Cola Co stock and 40% invested in Gas Co stock. Calculate the volatility by a Using the formula Ver(R) =w SP(R)2+w SD(R) +2ww, Corr (R1,R2)SD(R) SD(R) b. Calculating the monthly returns of the portfolio and computing its volatility directly c. How do your results compare a Using the formula