What is the concentration, in mol/L, of phosphoric acid in a 355 mL can of soda if it takes 19.50 mL of 0.500 M NaOH to completely titrate it? Phosphoric acid reacts with sodium hydroxide according to the following balanced chemical equation:

H3PO4(aq) + 3 NaOH(aq) 3 H2O(l) + Na3PO4 (aq)

Do not use units in your answer. Use 3 significant figures in your answer.