Question 2If $~\begin{array}{r|l}a&b \\ \hline c&d\end{array} = a\cdot d-b\cdot c,$ what is the value of $~\begin{array}{r|l}3&4 \\ \hline 1&2\end{array}~?$$-2 $$-1 $$0 $$1 $$2 $