You will shorten the life of the battery. Only add Distilled water to a battery.
My question is why would anyone do this? But since you asked. It will ruin the battery.
The car will then be unable to start.
Nothing. The battery is sealed an no harm will be done.
it will arch out and melt the knobs on your battery and your cables
add water and charge the battery
Nothing it will not harm the battery at all. It is sealed from outside elements. I do not mean putting it under the water as that would short it out. But to rinse it off is fine.
they have to be recycled and they wont work.
THE BATTERY WILL GO DEAD
Car batteries are filled with sulfuric acid, not water. The battery fluids get "topped up" with distilled water if they get low.
distilled water
If you can see the plates in the battery add distilled water to top it off.