In Problems $1-4,$ without the use of software, replace the question mark with what the

output would be if the scripts were executed in MATLAB.

$1$

$A=\left[\begin{array}{ccccccccccccc}1& 5& -1& 0\text{;}2& -3& 7& 4\text{;}1& 0& 6& 4\text{;}-1& 1& 0& 9\end{array}\right]$;

$w1=[1$;$0$;$-1$;$0]$;$w2=[3$;$0$;$-2$;$1]$;

$B=A$;

$B($:$,2$:$3)=[w1,w2]$;

$B=?$

$3$

$B=$diag$(diag(A,1),1)+$diag$(diag(A,-1),-1)$;

$C=$diag$(diag(A))+$triu$(B)$

$C=?$