Depends on tem. of water but you can get maybe 30 gal. before it starts getting too cold.
In most cases, about 15 minutes.
That depends on how much water is drawn from the tank and how often it is drawn.
As high as the highest setting available on the tank.
14 hours
how long does it take for hot water after lighting water tank its gas?
20 years at least, provided the hot water heater is serviced and maintained by a plumber once a year.
100 gallon.
The hot water tank might be undersized for your usage.
fret
75 gallon
10 awg
One gallon of water in the summer would last a person about one day in a hot desert.
A thirty gallon water heater should be sufficient.