Organic matter in a 0.95 g sample of burn ointment was removed by gravimetric burning method. A sparingly soluble ZnC2O4 precipitate was formed when the remaining solid ZnO residue was treated with (NH4)2C2O4 after dissolving in acid. When the solid was filtered, washed and dissolved again in dilute acid, 38.00 mL was spent as a result of titration of the released H2C2O4 with 0.02 M KMnO4. Calculate the percentage of ZnO in the sample and write the necessary reactions