URL	Title	Id
http://digfir-published.macmillanusa.com/astro_interactive_exercise/ie_planetary_orbits_and_configurations.html	Chapter 1. Planetary Orbits and Configurations	51335d9bb11c0f4b02000000
http://digfir-published.macmillanusa.com/astro_interactive_exercise/ie_planetary_orbits_and_configurations_dlap.xml	DLAP questions	51335d9bb11c0f4b02000000