If we breathe out carbon dioxide, why does CPR work? Why does modern CPR training de-emphasize rescue breaths? CPR manuals talk about doing 100-120 chest compressions per minute - why so much faster than the average pulse of around 60-80? What does Michael Jackson have to do with CPR?

Is it ok to pee in the swimming pool? Is pee poisonous or sterile? Which famous swimmers admitted to peeing in the pool? Why is it ok for sea creatures in the ocean, if all the creatures are peeing in there? How does urine indicator dye work? (hint it doesn’t)

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