Evaluate

$e^{xy}dA$

using a change $of$ variables, where $Dis$ the region $in$ the first quadrant bounded $by$ the

hyperbolas $xy=1$ and $xy=4,$ and the lines $\frac{y}{x}=1$ and $\frac{y}{x}=3.$ Sketch both the original

and new region $of$ integration, $D$ and $D^{*}.$