Calculate 5 different frequencies for C4 (Middle C), rounding each, if necessary, to the nearest 0.001 Hz. Show your work and name the tuning system used in each case. For each of these, A4 must have a frequency of 440 Hertz, and an octave must have 12 half-steps (as is normal). [Each correct answer after the first is worth half a point.]

[Hint: Different means duplicate frequencies are not allowed! If you come up with the same number two or more ways, you'll only get credit for one of them. There are many possible answers here; you only need to come up with five.]