reflex angle
there is no symbol, you just say angle A is adjacent to angle B
It is a right angle that measures 90 degrees and it has a special square like symbol
angle brackets
I think it is just called the right angle symbol
The sign for a vertical angle is......(I don't know actually >.
right (apex)
The Greek letter theta
It is a 90 degree right angle that has its own special symbol which looks like a small square in the corner.
See character code '0xD0' in the 'Symbol' font on a Windows computer.
It has usually a red box at the vertex and is called a "right angle."
A cone shown in a circle