Which kind of molecule gives a cell membrane it’s fluidity? 1. carbohydrates 2. phospholipids 3. proteins 4. nucleic acids

How do you date a sample of rock that you suspect as being one of the earliest on earth

Which kingdom includes some organisms that have no nucleus and can live in an environment with an extremely high salt content

What are the two causes of density in deep current waters? a. salinity (how much salt) of the water and high temperaturesb. salinity (how much salt) of the water and low temperatures c. oxygen content of the water and high temperatures. d. oxygen content of the water and low temperatures