62.5%
5/8 = 0.625 then multiply by 100% to get in terms of percent of 62.5%
Formula is π * r^2
π = about 3.14 and the radius is half of the diameter so 28/2 = 14
3.14 * 14^2 = 615.44
B
Supplementary angles add up to 180 degrees more than the other, you can formulate an equation 180=(100+x)+x80=2x so, x=40 the other angle is 100 degrees more. So, the angle lengths are 40 and 140 degrees.
I believe it would be B but I'm not 100% sure. Like i warn everyone, TRUST SOMEONE ELSE BEFORE TRUSTING ME. I would hate to see you get the wrong answer cause of me...
Best Hopes,
Cupkake~