Answer :

It's the second answer. Why?
Let's x be the weight of the art book. Now Let's translate the English into math language:

4x -4/5 = 2¹/₅

4x = 4/5 +2¹/₅
4x = 4/5 + 11/5

4x = 15/5 = 3 
and x = 3/4 of a pound