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Write the empirical chemical formula of calcium with a mass percent of 38.8, phosphorus with a mass percent of 20.0, and oxygen with a mass percent of 41.3.

When a spring is compressed, the energy changes from kinetic to potential. which best describes what is causing this change?

Give the set of reactants (including an alkyl halide and a nucleophile) that could be used to synthesize the following ether: draw the molecules on the canvas by choosing buttons from the tools (for bonds and charges), atoms, and templates toolbars, including charges where needed. ch3ch2och2ch2chch3 | ch3