1) (1/2)

= (2

= 2

= 1/4 - 16

= -15 3/4

= -63/4

2) Change the sign on the second term and you have it. (-1*-4=+4) The terms don't add. You can factor out xy

3) (5ab

^{2}- (1/4)^{-2}= (2

^{-1})^{2}- (4^{-1})^{-2}= 2

^{-2}- 4^{2}= 1/4 - 16

= -15 3/4

= -63/4

2) Change the sign on the second term and you have it. (-1*-4=+4) The terms don't add. You can factor out xy

^{4}, but "simplify" generally means to multiply it out.3) (5ab

^{2}/c^{3})^{2}= 25a^{2}b^{4}/c^{6}