Give a drawing or screen not of your circuit with the green LED illuminated at 49°C and another drawing or screenshot with the red LED illuminated at 50°C. Explain how your circuit works. Explain your choice for any voltage sources Explain your choice of resistor values. 

Designing a sensor circuit (20 marks)

This question asks you to design a circuit to sense a temperature and illuminate a green fight for temperatures of 49°C or below; and a red warning light in all other cases. You are recommended to use no more than 500 words in your answer to this question.
You are required to design an open-loop op-amp circuit that will sense the temperature so that a green LED is lit when 49°C or below. A red LED is lit otherwise.
You can assume that both the LEDs have a voltage drop of 2 V and require a current of about 2OmA (more specifically in the range 19-21 mA).
You should use the Omega 44004 thermistor in a Wheatstone bridge for this application. The Wheatstone bridge should have its own power supply.
If you use Multisim Live to design your circuit, to make the voltage drop across the LEDs 2.0 V, click on the * button to open the configuration pane and change the value of the Emission coefflcient to N = 2.72.
It is acceptable for your illuminated LED to switch from green to red above 49°C, but the red LED must be illuminated at 50°C

a. Give a drawing or screen not of your circuit with the green LED illuminated at 49°C and another drawing or screenshot with the red LED illuminated at 50°C. Resistor values must be shown in your drawings.  (10 marks)

b. Explain how your circuit works. Explain your choice for any voltage sources Explain your choice of resistor values.  (10 marks)