At the local drive in movie theater, there was a sign that said listening to your radio in accessories mode is equivalent to starting your car once. Is this really true?
Depends on volume level.
It’s a good guess, but it depends upon car engine size, battery size, condition of car engine, starter, battery, size of radio etc…
Two hours of radio time was the number I used back when I was a teenager and would go ‘parking.’ It only failed me once.