If you mean you connected the jumper cables around the wrong way then you may have blown the amp in the stereo. Speakers shouldn't be affected.
I've never tried that, but I am pretty sure the battery would no longer work.
I think diz nuts last longer
Yes The larger the battery, the more voltage the battery has.
Dead battery -will no longer charge.
the battery will no longer work.
See this link.
Energizer and other battery brands have an amino acid that gives the battery power.
A language that is no longer spoken is known as a "dead language." These languages are no longer used in everyday communication and have no native speakers.
energizer
The battery is as flat as a pig's nose !
Yes, energy is stored in a battery
A battery can last from 1 year to many years. You change it when it no longer will start the car or when it no longer will hold a charge.