She carries out an experiment to standardize (determine the exact concentration of) a sodium hydroxide solution. To do this, she weighs out a 1.3009 g KHP (potassium hydrogen phthalate (KHC8H4O4). KHP (molar mass 204.2 g/mol) has one acidic hydrogen. Gladys dissolves the KHP in distilled water, adds phenolphthalein as an indicator, and titrates the resulting solution with the sodium hydroxide (NaOH) solution to the endpoint. The difference between the final and the initial buret readings indicates that 41.20 mL of the sodium hydroxide solution is required to react exactly with the 1.3009 g KHP. Calculate the concentration of the sodium hydroxide solution (in mol/L).