1. The problem statement, all variables and given/known data Stress described as: S(t) = a0 + a1X(t) + a2X2(t) where X(t) is a the random displacement, a Gaussian random process and is stationary. Determine the autocorrelation function of S(t) (hint: remember a nice formula for the evaluation of high order moments of Gaussian random variables). 2. Relevant equations Rxx(T) = E[X(t)X(t+T)] 3. The attempt at a solution I am unsure of how to approach the problem using the above equation. Please advise. I can do the math I just need to see the setup with the proper functions plugged in.