Please help thank you. :)

Select the correct answer from the drop-down menu. subtracting 3xy^2 from 8xy^2 gives the same result as the expression. [tex]3xy ^{2} - 8xy ^{2} [/tex][tex] { - 7xy}^{2} - {2xy}^{2} [/tex][tex] {7xy}^{2} - {2xy}^{2} [/tex]

8000 + 8800 + 8000 + 8 million + 80 trillion + another a katrillion equals

Which of the following contains a variable?