Thanks for the help. That attachment really helped clarify a question we had.. mainly how to figure out the frequency from the RC time constant in that circuit.
So.. if you have another moment, could you verify the math in the circuit?
If C1 = 10uF = 1.0^10-6 = 0.000001 = 10 * 0.000001 = 0.00001 F
R3 = 22000 ohms
The RC time constant = 0.00001 * 22000 = 0.22 seconds or 220 milliseconds
Since R2 < R1 the frequency for the circuit is 0.455 / 0.22 = 2.07 Hertz
2.07 Hertz is very close to the flash rate of the LED we observed when we built the circuit on the breadboard.
Multisim is showing a period of about 120nS which is of course way way faster than what I observed when my son and I put the circuit together on the breadboard.
I just wish there was a way to fix Multisim so the program output was correct. Very frustrating. I'm guessing there is a way to run the simulation correctly, but I certainly can't figure out how to do it so far.