Fuel line

I have a 2001 Buick Century and a fuel line under the car is leaking. The part leaking is under the drivers seat area. I was wondering if anyone could tell me what size line it is so I can go to the parts store and get line and repair it.

I'm guessing 3/8" on supply, 5/16" on return.....just measure the outside diameter with a ruler.....

If it it rusted through in one area it would be good to inspect the entire length. Replacing a full coil of steel is less expensive than replacing several sections once the extra fittings are considered.