Please answer the question and write down the solution step by step. Thank you! Suppose that you have a sample of 500 observations on two random...

Please answer the question and write down the solution step by step. Thank you!

 Suppose that you have a sample of 500 observations on two random variables: price denoted as X, and profit, denoted as Y. So you observe {xi, yi} for i=1,...500. Write down the formula for sample mean and sample variance of X and Y as well as the sample covariance between X and Y