A sample of an iron ore is dissolved in acid, and the iron is converted to Fe2+. The sample is then titrated with 47.20 mL of 0.02240 M MnO4– solution. The oxidation-reduction reaction that occurs during titration is(a) How many moles of MnO4– were added to the solution? (b) How many moles of Fe2+ were in the sample?(c) How many grams of iron were in the sample? (d) If the sample had a mass of 0.8890 g, what is the percentage of iron in the sample?