what do the tropic of capricon, tropic of cancer lines, artic, an antartic circles represent?

Answer 1

These articles have your answers.

http://en.wikipedia.org/wiki/Tropic_of_Capricorn

http://en.wikipedia.org/wiki/Arctic_Circle

Note that it's ARCTIC and ANTARCTIC.

Answer 2

The Tropic of Capricorn line represents the farthest south direct sunlight goes.

The Tropic of Cancer line represents the farthest north direct sunlight goes.

Those are all that I know. Hope I helped!