The following data was obtained after 25.00ml of benzoic acid was titrated with potassium hydroxide.

Volume of KOH used:
Trial 1: 27.80ml
Trial 2: 27.88ml
Trial 3: 27.66ml

Initial pH: 3.125
pH at 13.92ml: 5.013

Find the Ka for this sample of citric acid and the concentration of the benzoic acid

(im completely lost)

Where did the citric acid come from. I assume it's legal to look up the Ka for benzoic acid.