Q-4) (25 pts): Assume that xIn] As[n] + wn] for n 0,1.-1 are observed, where win] zero mean noise with covariance matrix C is and sIn] is a known signal. The amplitude A is to be estimated using a BLUE. Find the BLUEand discuss what-happens is s = [s[0] s[1] s[N- 1]]"is an eigenvector of C. Also find the minimum variance Q-4) (25 pts): Assume that xIn] As[n] + wn] for n 0,1.-1 are observed, where win] zero mean noise with covariance matrix C is and sIn] is a known signal. The amplitude A is to be estimated using a BLUE. Find the BLUEand discuss what-happens is s = [s[0] s[1] s[N- 1]]"is an eigenvector of C. Also find the minimum variance