Two sequences x$1($n$)$ and x$2($n$)$ are shown in Fig. $1.$ For each of the following, write an equation for

the sequence in terms of shifted sample sequences and sketch the sequence.

a$)2$x$1($n$)$ vs$.$ n

b$)-3$x$2($n$)$ vs$.$ n

c$)[2$x$1($n$)-3$x$2($n$)]$ vs$.$ n

Fig. $1$