9. Consider the following MA(1) process:
Yt = et + 0.1et-1
where et is a white noise process with zero mean and variance Ļ^2.
(a) Calculate the variance of Yt.
(b) Calculate the autocovariance Ys for s = 1,2.
(c) Calculate the autocorrelation ps for s = 1,2.
(d) Show that the partial autocorrelation, β2, is given by
Ļ^2/(1+0.1^2)