A certain volume of NaOH(aq) is titrated against HCl(aq) in a well-insulated vessel with constant st — Laboratory Chemistry Chemistry Question

A certain volume of NaOH(aq) is titrated against HCl(aq) in a well-insulated vessel with constant stirring. Each solution is initially at 22.0 °C, and the temperature of the reaction mixture is monitored after each 2.0 mL of hydrochloric acid is added.

The data in closed circles correspond to an experiment conducted with 20.0 mL NaOH solution and 1.0 M HCl. The open circles were carried out using the same concentration but a different volume of NaOH solution, and using a different concentration of aqueous HCl. Which volume of NaOH and concentration of HCl correspond to the conditions that give the open circles?