What types of gases were found in the primordial earth?

Why did adult crab numbers decline in he ecosystem, even though sea stars were still available?

Easy 6th grade work! 100 points! i need fast! compare the parts of a cell and the cell as a whole to another common nonliving system (i.e., a car, a city, describe the parts of a cell and their primary function.

Creating new things to solve problems and improve life depends on the close interaction of which two fields?