Help with this problem, please

The center of the circumscribed circle lies on line segment and the longest side of the triangle is equal to the of the circle.

Find the interior angle of a regular polygon which has 6 sides

Paco orders an ice cream for $1, but realizes his wallet is at home and he only has 3/20 of $1 with him. if his mom pays the remaining 7/20 of the dollar, how much will she pay? $0.05 $0.15 $0.85 $0.95