Not very long, alcohol dehydrates your body.
They are very useful to our body as they are needed for growth and tissue repair
Not for a very long time.
Alcohol is useful to cleanse things. Alcohol can kill bacteria. Therefore it is often used in a disinfectant. Most of the time it's 70% alcohol 30% water
Rubbing alcohol is a very useful first aid product. It can be used for many different things. The shelf life of an open bottle of rubbing alcohol is usually a year, but check the use by date.
Swelling feet is usually caused by water tension and uneven blood flow throughout the body. Alcohol causes dehydration of the body, so it is very unlikely.
The human body metabolizes alcohol naturally. Some leaves the body through respiration and perspiration. However, most is broken down in the liver.
Alcohol is good for the body if consumed in moderation.
Yes the alcohol causes the body to become de-hydrated so it is very important to remain hydrated and drink plenty of water ideally before, during and after consumption of alcohol.
As an anesthetic and disinfectant? When was "back then?"
Big body with lots of reserved food like fats absorb alcohol very slowly. Thin people get quick kicks after a few pegs.
The body does in fact naturally produce alcohol on a daily basis. The amount produced, though, is generally metabolised over a given day and very small. The amount of alcohol within the body that an ETG can detect varies from individual to individual depending on several factors - including diet.