Aspirin, C9H8O4, is prepared by reacting salicylic acid, C7H603, with acetic anhydride, C4H603. Water is a byproduct. A student is to prepare 25.0 grams of aspirin using a 50.0 % excess of acetic anhydride while exepecting a 65.0% yeild. How many grams of each ractant should the student use.