Temple University: Gerardo Mendoza's and Dan Reich's "Calculus on the Web"

Click the link to Book I, and click on the "Index" button. Click on button 26 (A missing value). Work on problems 15-26. Return to the "Index," and click on button 27 (Discontinuities of simple piecewise defined functions). Complete problems 1-10. If at any time the problem set becomes too easy for you, feel free to move on. 

Click http://cow.math.temple.edu/ link to open resource.