The circumcenter is the center of the circle which goes through the triangle's vertices, so the circumcenter of the triangle and the center of that circumscribed circle MUST be the same point.
The same goes for the incenter and the center of the inscribed circle, though these will not, in general, be the same point as the circumcenter.
Okay so in a gallon there are 16 cups, in this case 100 cups is equivalent to 6.25 gallons. 6.25 times 3.12= 19.5
Therefore $19.5 is how much the gas cost!
The answer is what is shown on the phone
The first answer is figure B
the second is figure A because all angles are equal
the third is Hex regular
the 4th is octagon not regular
the 5th is hex regular
merry christmas my apologize for being to vague with my last answer