Total m of neutrons in 7 mg of C-14 isotope is___?

(0.007 g C-14) x [(1 mole C-14)/(14 g C-14)] x [(8 moles neutrons)/(1 mole C-14)] x [(6.022x10^23 neutrons)/(1 mole neutrons)] x [(1.674927351x10−27 kg)/(1 neutron)] =4.03x10^-6 kg