A student prepares an aqueous buffer solution by mixing \(100.\text{ mL}\) of \(0.20\text{ M }\text{HC}_2\text{H}_3\text{O}_2\text{(aq)}\) with \(100.\text{ mL}\) of \(0.80\text{ M }\text{NaC}_2\text{H}_3\text{O}_2\text{(aq)}\) at \(25\ ^\circ\text{C}\).

The student then divides the resulting mixture into two equal \(100.\text{ mL}\) samples. To Sample 1, the student adds \(0.020\text{ mol}\) of \(0.020\text{ mol}\) \(\text{HCl}\). To Sample 2, the student adds \(0.020\text{ mol}\) of \(\text{NaOH}\). Assuming the volume changes are negligible, which of the following best predicts the effect of these additions on the \(\text{pH}\) of the two samples?