Answer:
15
Step-by-step explanation:because u add them all up
7 = 2n-14 The word. Is. Means equal
This is a triangular prism.
The lateral faces are triangles; this means that the two bases are parallel to one another. This makes it a prism instead of a pyramid.
The bases being triangles makes it a triangular prism.
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:

Distance = rate times time. Thus,
d = (68 mph) (5.25 hrs) = 357 miles (answer)