Can one swim in petrol? What would happen? Would one float?sink?
You'd sink. (And there are other reasons not to try this at home.)
The density of petrol is less than 75% that of water. (Ref)
Cheers -- sylas
Try it and report back your findings. Make sure not to fill the pool too high. You want to be able to bob up and down off the bottom to reach the edge, if swimming is too strenuous. And, ah, don't breath doing it.
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