Please use econometrics to solve the following problems, preferably with detailed steps, thank you very much!

3. Consider a stationary second-order autoregressive process y = 40 + a2y1-2 + Et where & - WN(0, ) and a2# 0. a. Find the mean and variance of y b. Find cov(ys, yx-1) and cov( yy-2). c. Find the autocorrelations pi and P2. d. Find the partial autocorrelations 011 and 022. 3. Consider a stationary second-order autoregressive process y = 40 + a2y1-2 + Et where & - WN(0, ) and a2# 0. a. Find the mean and variance of y b. Find cov(ys, yx-1) and cov( yy-2). c. Find the autocorrelations pi and P2. d. Find the partial autocorrelations 011 and 022