Math Review

$($a$)$ Summation notation: Obtain ${\displaystyle \underset{i=1}{\overset{n}{}}}{z}_i$ for the following cases with $n=3$ and $i=1,2,3$ :

$z_i=5$

$z_i=i$

$z_i=i^2$

$z_i=(i-2{)}^2$

$z_i=\frac{3}{i}$