Q1. 8.5 A liquid-level control system can be configured in either of two ways: with a control valve manipulating flow of liquid into the holding tank (Fig. E8.5a), or with a control valve manipulating the flow of liquid from the tank (Fig. E8 5b ). Assuming that the liquid-level transmitter always is direct-acting, Figure E8.5 (a) For each configuration, what control action (direct or reverse) should a proportional pneumatic controller have if the control valve is air-to-close? (b) If the control valve is air-to-open