$1\mathrm{.}2,3$ and $4$ Evaluate the line integral by two methods:

$($a$)$ directly and

$($b$)$ using Green's Theorem.

$o{\displaystyle \underset{C}{\overset{\phantom{}}{}}}{y}^{2}dx+x^{2}ydy,C$ is the rectangle with vertices $(0,0),(5,0),(5,4),$ and $(0,4)$