(b)	Consider a system where the input (), noise () and the output () are related by the following equation:

() = 0.9( - 1) + ( - 2) + () + 0.5( - 1)

(i)	Design a Standard Minimum Variance Controller (SMVC), if the controller is use to optimize the variance of the system output.

(ii) Examine the minimum output variance by using SMVC

(iii)

Based on your answer in Question A2(b)(ii), determine and explain either the controller is suitable or not to be used for this plant.