Since he cannot cut out a piece of the floor, which steps should he perform to collect the saliva sample?

Why does it matter if osmosis is put into a “scab” or a “nosebleed? ” where would that leave him?

Which of the following is an eon in the time scale? phanerozoic proterozoic archean all of the above

Which of the following is a reason why early living organisms on earth could not have survived on the surface? 1. the lack of an ozone layer 2. the lack of oxygen in the atmosphere 3. the fact that these organisms were single-celled