1. you know if you put paracetamol in coke it froths up like crazy? how come if you swallow paracetamol with coke it doesn't froth up and make you choke? i suppose the answer is it goes down too fast but i'm not sure that it does.
2. when you get in the bath or a swimming pool, how do your insides not fill up with water? it's not like your anus and urethra are airtight is it?