45.5 mL of aqueou 0.255 M Pb(NO3)2 i mixed with 21.9 mL of 0.415 M NaCl. The equation for the precipitate reaction i: Pb(NO3)2 (aq) 2 NaCl (aq) --> PbCl2 () 2 NaNO3 (aq)

The concentration of NO3- ion in the reaction olution i _____ M.