Answer
Please see the figure attached.
Work Step by Step
The contour map of $f\left( {x,y} \right) = xy$ with level curves $c = - 3, - 2, - 1,0,1,2,...,6$ is obtained by plotting the curves:
$c = xy$ for $c = - 3, - 2, - 1,0,1,2,...,6$
The contour interval: $m=1$.
