test tomm so plz reply back fast

Question

a concrete bridge over a river has an underside in the shape of a parabolic arch. At water level, the arch is 30 mwide. it has maximum heigt of 10m above the water. the minimum vertical thickness of the concrete is 1.5m.

1-find the algebraic relation that represents the shape of the arch?
2-what is the vertical thickness of the concrete 3m from the centre of the arch?
3-if the water level rises 2m, how wide will the arch be at this new level?

can u plz explain each answer in detail as soon as possible plz

Answer 1

http://www.jiskha.com/display.cgi?id=1239932633

I know how to do your question, but I don't feel like doing so.
After all, I can do as I please.

Answer 2

hahahaahah
thats k i figured it out

Answer 3

Reiny -- Point well taken!