Wang and Taha described an interesting application of potentiometry, which they call batch injection. An ion selective electrode is placed in an inverted position in a large volume tank, and a fixed volume of a sample or a standard solution is injected toward the electrode's surface using a micropipette. The response of the electrode is a spike in potential that is proportional to the analyte's concentration. The following data were collected using a pH electrode and a set of pH standards. Determine the pH of the following samples given the recorded peak potentials: (a) tomato juice, 167mv; (b) tap water, 27mv; coffee, (c) 122mv