Which expression is equivalent to (3a)^-2
1/9a^2
1/3a^2
3/a^2
9/a^2

Anyone know? will mark brainliest if correct

Atextile fiber manufacturer is investigating a new drapery yarn, which the company claims has a mean thread elongation of 12 kilograms with a standard deviation of 0.5 kilograms. the company wishes to test the hypothesis upper h subscript 0 baseline colon mu equals 12 against upper h subscript 1 baseline colon mu less-than 12 using a random sample of n equals 4 specimens. calculate the p-value if the observed statistic is x overbar equals 11.8. round your final answer to five decimal places (e.g. 98.76543).

Which is f(5) for the function –2x2 + 2x - 3?