In key signatures with sharps the key is

Question

one half step from the last sharp
the next to last sharp
one half step up from the last flat
one whole step from the last sharp

Answer 1

In key signatures with sharps, the key is one half step up from the last sharp. For example, if the last sharp in the key signature is C#, then the key is D major (or B minor), which is one half step above C#.