Achemical substance that oganisms require to live

Why should the united state be concerned about air pollution in china?

Which of the following statements most accurately describes convergent evolution? the process in which two similar species evolve separately from each other and share similar characteristics the process in which a single species evolves into two or more new species the process in which two entirely different species evolve in response to each other the process in which two different species evolve separately from each other but still share similar characteristics

In this experiment, the was intentionally manipulated. it is the independent variable. the dependent variables that were measured were the