A $2\mathrm{.}568gm$ sample of brass, when treated in a way, it yields $0\mathrm{.}133$gmSnO$2.$The$\%Sn$ in the brass is $($Atomic mass in $g\frac{m}{m}ol,Sn=119,O=16)$:

a$.40\mathrm{.}8\%$

b$.80\mathrm{.}4\%$

C$.4\mathrm{.}08\%$

d$.8\mathrm{.}04\%$