3/4" ID x 10 Ft High Pressure Braided Clear PVC Vinyl Tubing Flexible Vinyl Tube, Heavy Duty Reinforced Vinyl Hose Tubing, BPA Free and Non Toxic

Q: Can this be used with gasoline?

Yes you can use it with gas just keep a eye on it and when it starts to get hard change it out . I use it on my race bike and never had any trouble .

Q: Is it available in 15 ft, could you cut it into two part?

Of course, 25 feet tubing can be cut to any size you want, easily to cut by any cutting tool.

Q: Will it work to pressure up a train horn?

I used mine for a fuel filter on diesel truck. Depends on how much pressure you are pushing through it. If you want my opinion, I would say no.. but that's just my opinion, and the difference in my hose is mine is not braided where this hose is, so it may. Hope I helped you

Q: Can you drive over it?

If you drive over this hose, I don't think you'll harm it, but like most any other hose it will be mashed while your car wheel is on top of it. It will not retain its shape. It is not especially stiff.