How long can a Submarine stay underwater?
How long ago were Submarines invented?\xa0How are Submarines able to sink?\xa0How does a Submarine make air for its crew to breathe?\nHave you started your FREE TRIAL of Who Smarted?+ for AD FREE listening, an EXTRA episode every week & bonus content? Sign up right in the Apple app, or directly at\xa0\nGet official Who Smarted? Merch: tee-shirts, mugs, hoodies and more, at Who Smarted?\nFor more information about our other projects, including bespoke branded podcasts and series for your company, check out \xa0Atomic Entertainment.