need math on 3. From the balanced Equation (6) and the results from step # 2 calculate the number of moles of acid titrated.

(6) is CH3 COOH (aq) NaOH (aq) → Na+(aq) + CH3COO- (aq) + H2O
results from #2 is 7.2*10^-3 L

moles = M x L