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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.

As you watch a surfer ride a wave towards the shoreline, what is the shoreline? a) displacement reference b) reference point c) coordinate plane d) cartesian boundary

What kind of intermolecular forces act between a hydrogen fluoride molecule and a hydrogen peroxide molecule? note: if there is more than one type of intermolecular force that acts, be sure to list them all, with a comma between the name of each force.