Question 72
A $3 \times 4$ grid is given. Answer the number of possible cases to write a number among $1$, $2$, $3$ or $4$ in each square so that
* no number appears twice (or more) in the same row, and
* no number appears twice (or more) in the same column.
* no number appears twice (or more) in the same row, and
* no number appears twice (or more) in the same column.