It is not good to use tap water in any battery, no matter what voltage. You should use distilled water only.
Yes, you can use a twelve volt car battery charger. Be sure to set it on low.
No
No, it will overcharge the 6 volt battery.
No it will not work
No, the battery will be overcharged and battery damage will occur if it is done.
No.
No
can 6 ,12 volt battery be wire to make in to one 24 volt battery for solar use in home
12 volt battery
Absolutely not! It is a 14 volt drill. Use a 16 or 18 volt battery will destroy the drill in short order. It will run but not for long.
It is not recommended to replace a 14 volt battery with an 11 volt battery as the voltage difference may affect the performance of the device. It is important to use the correct voltage battery specified by the manufacturer to prevent damage to the device.
use two 12 volt batteries in series.