42.8 mL of aqueous 0.255 M Pb(NO3)2 is mixed with 16.4 mL of 0.415 M NaCl. The equation for the precipitate reaction is: Pb(NO3)2 (aq) + 2 NaCl (aq) --> PbCl2 (s) + 2 NaNO3 (aq)

The concentration of NO3- ion in the reaction solution is _____ M.