what is the difference between paradox, juxtaposition, and antithesis?

Answer 1

http://web.cn.edu/kwheeler/lit_terms_P.html
Scroll down and read about Paradox.

http://web.cn.edu/kwheeler/lit_terms_J.html
Scroll down and read about Juxtaposition.

http://web.cn.edu/kwheeler/lit_terms_A.html
Scroll down and read about Antithesis