$\begin{array}{1 1}(a)\;6.023\times10^{23}&(b)\;\large\frac{1}{9.108}\normalsize \times 10^{23}\\(c)\;\large\frac{6.023 \times 10^{54}}{9.108}&(d)\;\large\frac{1}{9.108\times 6.023}\normalsize \times 10^8\end{array}$
