Scientists are studying fertilizers to help grass grow in southern California. Fertilizer is any substance that can be added to soil to help plants grow in it. In other words, fertilizer makes soil more fertile. The scientists set up different plots of land that all use the same type of soil, but they use different types of fertilizer in each plot. Scientists then measure the grass growth in the different soils over time.

How should scientists set up the control group in this experiment?

Explain how the political influence of african americans leaders became weaker.

As scientist had investigated evolution from a variety fields they have found

Crinoids, also known as sea lilies, appear to be sea plants but are not plants at all. crinoids are an echinoderm species which uses anchoring structures called holdfasts to attach themselves to the sea floor. crinoids were most abundant in pennsylvania during the mississippian period, which ranged from 375 to 320 million years ago. fossils of the crinoids shows that during most of this time pennsylvania was that provided favorable conditions for crinoid growth. a) glacial terrain b) a dry and sandy plain c) mostly mountain ranges d) covered by warm, shallow seas