Here are the percentage returns on two stocks.

Month Digital Cheese Executive Fruit

January $14\%6\%$

February $31$

March $64$

April $814$

May $42$

June $46$

July $24$

August $82$

a$-1.$ Calculate the monthly variance and standard deviation of each stock. $($Do not round intermediate calculations. Round your answers to $1$ decimal places.$)$

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.$)$