Simulation Screen 1

          1. Click on the "Click to begin" button.
          

          Simulation Screen 2: To formulate the Function table and Boolean Expression for 4:1 multiplexer

          1. Select appropriate options from the drop down menu and formulate the function table.
          2. Click submit.
          3. If incorrect try again.
          4. If correct, select the correct expression defining the multiplexer. 
          5. Try again if answer is incorrect.
          6. Proceed to the next step. Click Next.
          

          Simulation Screen 3: Simulator Scene - To design, construct and verify the operation of a 4:1 multiplexer using 2:1 multiplexers 

          Design of 4:1 Mux using 2:1 muxes (refer figure).
          

          
          General instructions:
          1.     Click on the digital switch and click on the canvas.
          2.    Repeat step 1 for all required three inputs.
          3.    Click on the 2:1 mux symbol and then on the canvas at an appropriate position on the canvas. 
          4.    Repeat for the placement of 2nd 2:1 mux.
          5.    Click on the 3rd 2:1 mux and then on the canvas to place it at an appropriate position on the canvas.
          6.    Use the connection tabs and make the necessary connections.
          7.     Connect the output to the LED.
          8.    Simulate and verify the circuit.