A specimen of silicon is to be made $$P$$-type semiconductor for this one atom of indium, on an average, is doped in $$5 \times 10^7$$ silicon atoms. If the number density of silicon is $$5 \times 10^{22}$$ atom/$$\mathrm{m}^3$$ then the number of acceptor atoms per $$\mathrm{cm}^3$$ will be

A proper combination of $$3 \mathrm{NOT}$$ and 1 NAND gates is shown. If $$A=0, B=1, C=1$$, then the output of this combination is