Epps 7363-Assume That Zt ? Wn(0, ?2)

For each of the following models(a) xt = 0. 3xt?1 + zt(b) xt = zt ? 1. 3zt?1 + 0. 4zt?2(c) xt = 0. 5xt?1 + zt ? 1. 3zt?1 + 0. 4zt?2assume that zt ? wn(0, ?2) and express the model in lag polynomial notation, determine whether it isstationary and / or invertible. For model (a), find the MA representation.