Chapter 8, Problem 4CRQ

To determine

To fill: “The trace of the graph of $f\left(x,y\right)$ in the plane $z=k$ is the curve with equation _______ lying in the plane $z=k$. The projection of the trace of f in the plane $z=k$ onto the xy-plane is called the _________ of f. The contour map associated with f is obtained by drawing the _______ ______ of f corresponding to several admissible values of _______”.