In the lab, a weak acid is split into 2 equal volumes, and one portion is titrated with NaOH to an end point. Both solutions are then made equal in volume by adding deionized water. a. When equal volumes of the two solutions are mixed, the resulting pH is 3.40. Determine the value of K_a for the weak acid. b. Calculate how many milliliters of the solution containing conjugate base (the titrated weak acid) must be added to 30 mL of weak acid to make a buffer of pH 2.10. c. Calculate how many milliliters of 8.76 M of the solution containing the conjugate base (titrated weak acid solution) must be added to 10.0 mL of 0.500 M weak acid to make a buffer of pH 4.240.