3. [20 pts] Consider the idle speed control system of a fuel-injected engine shown in Fig. 2. Let T(s) be the closed-loop transfer function from R(s) to Y(s). Determine the sensitivity of T(s) with respect to G3(s). Air bypass H2(s) R(s) Speed command Fuel K5 K6 gain Manifold Dynamics G(s) G(8) G3($) Pressure Y(s) Engine H(s) speed Spark gain K4 Copyright 2017 Pearson Education, All Rights Reserved Figure 2: Idle speed control system.