Chapter 5
plotting how to, ellipse, 3D

 5.1 Generate a plot using x and y data
 5.2 Plot the surface described by 2D function
 5.3 Find the point of intersection of 3 surfaces
 5.4 How to draw an ellipse?
 5.5 How to plot a function on 2D using coordinates of grid locations?
 5.6 How to make table of \(x,y\) values and plot them
 5.7 How to make contour plot of \(f(x,y)\) ?