A conical air column will produce the same fundamental frequency as an open cylinder of the same length and will also produce all harmonics.

Conical air columns are employed in several of the woodwind musical instruments: oboe, bassoon, saxophone, and others.

How does one tuning fork produce resonance at three different lengths?

For tuning fork frequency Hz and temperature= T = C
T = F,

the speed of sound is v= m/s
v = ft/s = mi/hr.

The closed tube fundamental resonance will be produced at length L = cm = ft , which is 1/4 of a wavelength.

If the water is lowered to cm

the third harmonic of the longer column will be excited by the fork. Hz Hz

If the water is lowered to cm

the fifth harmonic of the column will sound along with the tuning fork. Hz Hz Hz