help with this please

Define the terms diene and dienophile as they apply to the Diels-Alder reaction. How many new bonds, and of what type ( or ), are created in a Diels-Alder reaction? What is the structure of the dicyclopentadiene? What diene and what dienophile could be used to prepare each of the following? b) How is the "exo" and "endo" of a bridged bicyclic compound defined? Why cannot cyclopentadiene be purchased directly from a commercial supplier