Factor. 81a^36−64b^16 a. (9a^6-8b^4) (9a^6+8b^4) b. (9a^18-8b^8) (9a^18+8b^8) c. (9a^6-8b^4)^2 d. (9a^18-8b^8)^2

Darren earned $663.26 in net pay for working 38 hours. he paid $118.51 in federal and state income taxes, and $64.75 in fica taxes. what was darren's hourly wage? question options: $17.45 $19.16 $20.57 $22.28