Please Help Me: Why would water have to be present on Earth before life?

The distribution of related animals and plants across the world

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

Number and variety of living organism; includes genetic, species, and ecological types