Final answer:
F Sharp and G Flat represent the same musical note, which is just below the staff line and is correctly referenced as both options 1) F# and 2) Gb. The beat frequencies produced by playing F, F#, and G simultaneously on a piano are 21 Hz and 22 Hz, respectively.
Step-by-step explanation:
The note represented by F Sharp/G Flat is enigmatic because it's the same pitch in Western music, known as an enharmonic equivalent. The correct answer to the question is that F Sharp (F#) and G Flat (Gb) refer to the same note, which is just below the staff line of a musical score. This note can be notated either as an F# or a Gb depending on the musical context, such as the key signature of the piece.
When three adjacent keys on a piano (F, F-sharp, and G) are struck simultaneously and produce frequencies of 349, 370, and 392 Hz, the resulting beat frequencies would be between each pair of notes. For F and F-sharp, the beat frequency is 370 Hz - 349 Hz = 21 Hz. Similarly, the beat frequency between F-sharp and G is 392 Hz - 370 Hz = 22 Hz. Therefore, the discordant combination produces beat frequencies of 21 Hz and 22 Hz.
Hence, Options 1 and 2 are correct.