To be fair, a metal subway car (provided they removed every piece of rubber, plastic and electronic component) is environmental quite neutral, as metal and glass are inert. In this case though, I'm pretty sure tennis ball contain plastic so it wouldn't be whise to just leave them in the open. If they were glass balls, it would be better.
bobo1900
joined 3 days ago
Even if you do everything you can to avoid these things, statistically adhd folks will do them more than neurotipical people