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Calculate the percent by mass of water in FeCl2 · 4H20.

Americium-241 undergoes fission to produce three neutrons per fission event. if a neutron-absorbing material is mixed in with this sample so that the rate of neutron production drops down to 1.8 neutrons per fission event, which will be effective at achieving a critical mass? check all that apply. remove a deflective shield surrounding the sample. remove absorbent material mixed in with the sample. compress the sample of americium-241.

Explain in detail of the four major scientific developments that spurred the formulation of the plate tectonics theory

The fact that the total amount of energy in a system remains constant is a(n)