89. A sample of a washing powder that contains a mixture of Na2CO3 and NaHCO3 is titrated with aqueous HCl and the followingresult is obtained:What is the mole ratio of CO32–to HCO3–in the washing powder?
(A) 2 mole CO32–: 1 mole HCO3–
(B) 1 mole CO32–: 1 mole HCO3–
(C) 1 mole CO32–: 2 mole HCO3–
(D) 1 mole CO32–: 3 mole HCO3–
(E) 3 mole CO32–: 1 mole HCO3–(一律送分)