My study group and I were working on our homework and we came
     across a problem in Part 2b. It asks for the number of address lines and
     in your book on Page 69, I see "address bits" and "word lines." Is address
     lines the number of bits required to differentiate between addresses or
     is it the actual number of lines?     

     << name withheld to protect the last minute questioner >> 

Address lines in this context is the same as address bits. Each bit generates a line to the decoder. The decoder in the "new" case would generate 60 word lines.

Yale Patt