There aren't any.
G-flat major.
The major scale with four flats is the key of A-flat major. In this scale, the notes are Ab, Bb, C, Db, Eb, F, and G. The flats in this scale are Bb, Eb, Ab, and Db.
Yes, G-flat major.
There are different rules. For major keys, the rule is this (by the way, # means sharp): C major scale- 0 sharps or flats G major scale- 1 sharp - F sharp D major scale- 2 sharps - F and C sharp A major scale- 3 sharps - F, C, G sharp E major scale- 4 sharps - F, C, G, D sharp B major scale- 5 sharps - F, C, G, D, A sharp F# major scale- 6 sharps - F, C, G, D, A, E sharp C# major scale - 7 sharps - F, C, G, D, A, E, B sharp. For major keys with flats: F major scale - 1 flat - B flat B flat major scale - 2 flats - B, E flat E flat major scale - 3 flats - B, E, A flat A flat major scale - 4 flats - B, E, A, D flat D flat major scale - 5 flats - B, E, A, D, G flat G flat major scale - 6 flats - B, E, A, D, G, C flat C flat major scale - 7 flats - B, E, A, D, G, C, F flat So as you might have noticed, in increasing order of sharps it is: F, C, G, D, A, E, B. And the increasing order of flats is B, E, A, D, G, C, F. If you notice the order of sharps is the opposite of the order of flats.
The B major scale has 5 sharps: F#, C#, G#, D#, A#.
Just one, and that would be F sharp.
The C major scale is the only diatonic (major) scale without sharps or flats. The notes are simply C, D, E, F, G, A, B and C.
C major has no sharps or flats.
The scale that has 2 flats is the key of B flat major.
C Major scale: C D E F G A B C (no sharps or flats) C Major chord: C - E - G
C D E F G A B C no sharps or flats
F sharp C sharp G sharp D sharp