Design a 1st order Butterwort​h low pass filter

Hey there... Really hope that u guys can guide me to solve these questions.. =)
Design a first order Butterworth low pass filter with cut-off frequency
fo = 20 kHz and the gain K = 1. You will need to simulate the circuit
using Multisim and shows that the circuit meet the required
specification.
i)Show all calculations steps and assumption made in your circuit design.
(DONE!)
ii)Show the circuit schematic with all the resistor and capacitor values labelled.(attachment)
iii)Perform frequency response analysis on the circuit and obtain the
bode diagram. The bode diagram should show the voltage gain (Vout /
Vin) in dB vs the signal frequency (0 to 100 MHz). Does the -3dB
cut-off frequency match the desired cut-off frequency fo = 20 kHz ?
Explain. From the graph, estimate the roll-off rate. (attachment)
I inserted my schematics and graph.. am i right?
Attachments:
Question 2a.zip ‏146 KB

Just an update for the community, in version 11 and 12 of Multisim, there are some circuit wizards available which can make designing some basic circuits easier. To access the filter wizard, go to Tools -> Circuit Wizard -> Filter Wizard. You can put in the parameters and Multisim will automatically generate the filter for you.
Hope this helps.
Regards,
Tayyab R,
National Instruments.

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