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Which of the following is always a reactant in a combustion reaction? oxygen nitrogen hydrogen carbon

Which of the following is not a good technique for managing used oil? a) have specific, labeled catch pans available for technicians who are collecting oil b) spills in your shop and any releases on pavement or outside should be poured down a drain c) do not use oil containers for antifreeze or other non-similar fluids d) be prepared for oil spills with the proper absorbents

Calculate the mass of 0.750 mol of the following substance. na3po4.