What accidental raises the pitch of a note by 1/2 step

The answer is a "sharp".

Explanation:

A sharp is a symbol that looks similar to a hashtag that is placed next to a note to raise its pitch up by half a step

the correct answer for this question is:

it is system invented in 1872 that produced the first illusion of movement. basically it was a disk with a series of drawings around the edge, showing the same object in slightly different poses. when it was spun, it created the illusion of movement.

found this online : )

b i think if not it should be a pretty sure but not