c
(c) $A = \left[ {\,\begin{array}{*{20}{c}}1&2&3\\1&4&9\\1&8&{27}\end{array}\,} \right]$
Let $c_{ij}$ be co-factor of $a_{ij}$ in $A$
Then co-factor of elements of $A $ are given by
${C_{11}} = \left| {\,\begin{array}{*{20}{c}}4&9\\18&{27}\end{array}\,} \right|\, = 36,\,{C_{21}} = \left| {\,\begin{array}{*{20}{c}}2&3\\8&{27}\end{array}\,} \right| = - 30,$$\,{C_{31}} = \left| {\,\begin{array}{*{20}{c}}2&3\\4&9\end{array}\,} \right| = 6$
${C_{12}} = \left| {\,\begin{array}{*{20}{c}}1&9\\1&{27}\end{array}\,} \right|\, = 8,\,{C_{22}} = \left| {\,\begin{array}{*{20}{c}}1&3\\1&{27}\end{array}\,} \right| = 24,$$\,{C_{32}} = \left| {\,\begin{array}{*{20}{c}}1&3\\4&9\end{array}\,} \right| = -6$
$\,{C_{33}} = \left| {\,\begin{array}{*{20}{c}}1&2\\1&4
\end{array}\,} \right| = 2$
==> $Adj(A)\,\, = \left| {\,\begin{array}{*{20}{c}}
{36}&{ - 30}&6\\
{ - 18}&{24}&{ - 6}\\
1&{ - 6}&2
\end{array}\,} \right|\,$
==>$Adj(A) = 36(48 - 36) + 30( - 36 + 24) + 6(108 - 96)$
==> $Adj(A) = 144$