What note is this and explain why

The answer to the question above is C#.

Explanation: The note shown is on the second ledger line above the staff. If the top line of the staff is F, then using half steps, you can go 4 half steps up to reach C#. The top line of the staff is F because the clef is a treble clef.  This means that the notes for each line are changed to E, G, B, D, F (in order).

answer; /// i believe that its (c) universal symbols;