C# Major
There is no key signature that has Bb and C#.
D major has a key signature of F sharp and C sharp D minor has a key signature of B flat
C# major A# minor
The key signature with 7 sharps is C-sharp major. In this key, the sharps are F-sharp, C-sharp, G-sharp, D-sharp, A-sharp, E-sharp, and B-sharp. Its relative minor is A-sharp minor, which also features the same key signature.
Only "B flat" is the key signature, then "C sharp" is the accidental.
B Major is the 1st major scale that CONTAINS A sharp and F sharp within its key signature but has a total of 5 sharps which are, F# C# G# D# A# F# Major also CONTAINS A sharp and F sharp within its key signature but has a total of 6 sharps which are, F# C# G# D# A# E# C# Major also CONTAINS A sharp and F sharp within its key signature but has a total of 7 sharps which are, F# C# G# D# A# E# B#
The key signature of D sharp major has nine sharps: F, C, G, D, A, E, B, and F.
D minor - more specifically, D harmonic minor (the version of the minor scale with a flat 6 and a sharp 7). However, you will never see a key signature with a B flat and a C sharp. The key signature will only contain B flat.
The major key with the most sharps is C-sharp major, which has seven sharps. The sharps in this key are F-sharp, C-sharp, G-sharp, D-sharp, A-sharp, E-sharp, and B-sharp. C-sharp major is often considered challenging for performers due to the complexity of its key signature.
TO FIND THE KEY FROM THE KEY SIGNATUREIf the key signature has sharps:The major key is the note above the last sharp in the key signature.The minor key is the note below the last sharp in the key signature.Ex: key signature with sharps f-c-g is A major or F-sharp majorIf the key signature has flats:The major key is the note of the next to last flat in the key signature. If there is only one flat, it is F major.The minor key is the note TWO notes above the last flat in the key signature.Ex: key signature with the flats b-e-a-d-g is D-flat major or B-flat minorIf the key signature has no flats or sharps:The major key is C.The minor key is A.TO CREATE THE KEY SIGNATURE FROM THE KEYThe sharps always go in this order: F-C-G-D-A-E-B-C (circle of fifths)If you are creating the key signature for a major key, keep writing sharps until the last sharp is the note below the key you need.If you are creating the key signature for a minor key, keep writing sharps until the last sharp is the note above the key you need.Ex: The key signature for B major and G-sharp minor is f-c-g-d-a.The flats always go in this order: B-E-A-D-G-C-F (circle of fourths)If you are creating the key signature for a major key, keep writing flats until the next-to-last flat is the key you need.If you are creating the key signature for a minor key, keep writing flats until the last flat is TWO notes below the key you need.Ex: The key signature for E-flat major and C minor is b-e-a.The key signature for C major and A minor has no flats or sharps.The key signature for F major and d minor has ONE flat (B-flat).
B-minor has no flats in it's natural key signature (of course, accidentals can always be added to alter a melody without altering the key signature). The key of b-minor (relative minor of D-major) has two sharps in its key signature; F-sharp(#) and C-sharp(#). If you wanted to play a b-natural-minor scale, you would play; B-C#-D-E-F#-G-A-B For a b-harmonic-minor; B-C#-D-E-F#-G-A#-B For a b-melodic-minor; B-C#-D-E-F#-G#-A#-B-A(natural, remove the sharp)-G(natural, remove the sharp)-F#-E-D-C#-B I hope this helps.
The naturals simply indicate that the five notes that were previously sharp, are no longer sharp. The key will be C Major, or a minor.