In order to determine what buffer to calibrate a pH meter for a pH titration of weak acid with a strong base, the titration endpoint is to be determined. The acid is formic acid and its estimated concentration is 0.2 M and 25.00 ml is to be titrated. The concentration of the sodium hydroxide will be about 0.1 M. Use this data to estimate the pH at the titration endpoint. What would be a good indicator for this titration?