Answer:
F
Step-by-step explanation:
Area of sector=pi*r^2*(theta/360) = pi*r^2*(45/360)
18*pi=pi*r^2*(1/8), r=12. Circumference is 24*pi
I'm sorry but the solution you proposed was a bit hard to follow, so I'll just post my solution: we convert "2 and 1/2" to a single fraction:

So, we know that 5/2 gallons cost 60 dollars, which means

To find the cost of a single gallon, we have to solve the equation for g:

For a more see orthocenter of a triangle .The orthocenter is the point where all three altitude of the triangle intersect. An altitude is a line which passes through a vertex of the triangle and is a perpendicular to the opposite side. Hope this helps :)