You hold a portfolio of securities which have had the following annual returns: {7%, 15%, -19%, 0%, 9%, 13%}.

What is the sample variance of the returns?

What is the sample standard deviation of the returns?

You believe that these returns are normally distributed. What is the probability that the return in any given year will exceed the arithmetic mean?

You believe that these returns are normally distributed. What is the probability that the return in any given year will exceed one standard deviation below the mean?