5: Consider the following control instrumentation diagram for a heat exchanger. TC TM Cold Stream Hot Stream a. Construct a control block diagram, labeling all signals and transfer functions. Make certain that you include valve and measurement sensor dynamics. Also include at least one important disturbance input. b. Should the control valve should be fail-open or fail-closed. Why? c. Based on whether the control valve is fail-open or fail-closed, is the process gain relating the manipulated valve position (or valve top pressure) to the measured temperature positive or negative