Here are the percentage returns on two stocks. Month Digital Cheese Executive Fruit January 14% 8% February 5 1 March 7 3 April 9 13 May 6 2 June 5 7 July 4 6 August 7 5 a-1. Calculate the monthly variance and standard deviation of each stock. (Do not round intermediate calculations. Round your answers to 1 decimal places.) a-2. Which stock is the riskier if held on its own? b. Now calculate the variance and standard deviation of the returns on a portfolio that invests an equal amount each month in the two stocks. (Do not round intermediate calculations. Round your answers to 1 decimal places.) c. Is the variance more or less than half way between the variance of the two individual stocks?