Which of the key signature has one sharp on the fifth line on the staff

Notice that the fifth note of the key of C (G) is the starting note of the key that has one sharp.

1. What key signature has 1 sharp in the beginning of the measure?
2. What are the key signatures for treble clef?
3. What is key signature in music?
4. What sharps and flats are in each key?

What key signature has 1 sharp in the beginning of the measure?

For example: a key signature of one sharp is either G major or E minor.
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Key signature.

What are the key signatures for treble clef?

Treble Clef Sharp Key Signatures

They are G, D, A, E, B, F#, and C#.

What is key signature in music?

Key signature, in musical notation, the arrangement of sharp or flat signs on particular lines and spaces of a musical staff to indicate that the corresponding notes, in every octave, are to be consistently raised (by sharps) or lowered (by flats) from their natural pitches.

What sharps and flats are in each key?

There is a key signature for each scale in minor and major scale. There are in total of seven flats and sharps, the flat looks like a "b" and the sharp looks like a "#". There are seven sharps~...
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List of key signatures.