90 degrees
rightangle
yes
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
None
by using rightangle triangle
1/360
90 degrees
a pirouette
22.5
a pirouette
A right angle turn is equivalent to 90 degrees. Therefore, one ninth of a right angle turn would be 90 degrees divided by 9, which equals 10 degrees. This means that one ninth of a right angle turn is a rotation of 10 degrees.