how many sharps in the key of a
A major A major (or the key of A) is a major scale based on A, with the pitches A, B, C♯, D, E, F♯, and G♯. Its key signature has three sharps.
Alt key On a Macintosh, the Alt key is called the Option key. It is not used to enter numeric character codes. Instead, keyboard letters and numbers are used. The diagram below shows the special characters a US Mac keyboard will produce when the Option key is pressed.[1]