Quinine is a weak base, with pkp = 5.10. What is the pH if a 25.0 ml solution originally containing 0.125 moles of quinine is titrated with HCl to the equivalence point, and if the combined total volume at the end is 56.0 ml? Select one: O a. 7.98 O b. 5.10 O c. 4.28 O d. 8.72