What molecule makes up 3/4 of the Earth's surface and all life could not survive without it?

What protects the lining of the stomach from acidic gastric juices?

Scientists discover two populations of mice on either side of a major river. the two populations have almost identical genes but the mice from one side cannot breed with mice from the other. this is most likely because

Toorale man murder mystery < - your lab link 1. how was the toorale man found? 2. what did archaeologists learn about the burial? why is the burial important? 3. what information were the scientists able to learn from the skeleton itself? 4. why is the question of whether the injuries came from a stone or steel weapon important? how could scientists distinguish between the different types of weapons? 5. what did the carbon dating and soil testing tell scientists about toorale man? why are the dates interesting for scientists?