Given a $KK$ confusion matrix for a K$-$class classifier, where $n_{ij}$ denotes number of instance of class $j$ predicted as class $i.$ Further, ${\displaystyle \underset{i}{\overset{?}{}}}{\displaystyle \underset{j}{\overset{?}{}}}{n}_{ij}=N$ is the total number of instances. Write expression for class$-$wise precision, recall, specificity, and F$1-$score. Compute these metrics for the following confusion matrix for the three classes, A$,$ B$,$ and C:

$(8$ marks$)$