The amount of grams of phosphorus that are recommended is 0.700 g
Why?
This is an unit conversion problem. To convert between units we use conversion factors. In this case the conversion factor we want is from mg to g, and this is relatively simple: 1000 mg = 1 g. Now, we arrange the quantities in the following way:
Conversion factors are really useful for converting units! Just remember to put the unit you don't want at the bottom, and the one you want at the top.
Have a nice day!
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