yes
A right angle turn is a 90 degree turn. Therefore, one ninth of a right angle turn would be a 10 degree turn.
The letter K. It has two acute angles, top and bottom between, the l and < and the inside angle of the < is a rightangle.
hypotenuse
by using rightangle triangle
1/360
22.5
a pirouette
a pirouette
A 45 degree turn is an angle
The ballet term for the 180 degree turn on one foot is 'pirouette'. Pirouettes can be double or triple or more, turning 180 degrees multiple times.
There is no particular name.