$(3pts)$ Consider the double integral

${\displaystyle \underset{R}{\overset{\phantom{}}{}}}$fdA$={\displaystyle \underset{-1}{\overset{0}{}}}{\displaystyle \underset{0}{\overset{1+x}{}}}fdydx+{\displaystyle \underset{0}{\overset{1}{}}}{\displaystyle \underset{0}{\overset{1-x}{}}}fdydx$

$(a)$ Sketch the region $of$ integration $R.$

Figure $2.$ Figure for Problem $5.$

$(b)$ Reverse the order $of$ integration $by$ completing the $limits.$

${\displaystyle \underset{R}{\overset{\phantom{}}{}}}$fdA$={\displaystyle \underset{\phantom{}}{\overset{\phantom{}}{}}},{\displaystyle \underset{\phantom{}}{\overset{\phantom{}}{}}},fdxdy$