Which expression is equivalent to (3^2) ^-2

a. - 81

b. - 12

c. 1/81

d. 1/12

C. 1/81

First simplify what's in the parenthesis

(3^2) = 9

Now your answer is:

9^-2

but there is no such thing as a negative exponent so write the expression as a fraction

1/9^2

and simply simplify so your answer is

1/81