The two possible frequencies could be ; 642 Hz or 712 Hz
Explanation:
For beats; fâ-fâ=fb where fâ=frequency of the first guitar, fâ=frequency of the second guitar, fb =frequency of beat
In this case, the two possibilities are;
fâ-fâ=fb or fâ-fâ=fb
fâ=677 Hz  and fb=35 Hz
then;
fâ-x=fb
677-x=35
x=677-35=642 Hz
or
x-fâ=fb
x-677=35
x=35+677 =712 Hz
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Frequencies and Beats ; https://brainly.com/question/1510332
Keywords : Frequency, beats, guitarist's, Hz
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