The angle passes 90 degrees plus an additional 55 degrees
m
The circumference of a circle of radius
is

So, in your case, the circumference is

The circumference is actually the length of the "perimeter", so the answer to questions 1 and 2 looks the same actually
4/9 divided by 2/3 divided by 5/6 = 4/5
when you divided by two fractions, you can flip the denominator and numerator and then mutiply