3^(-2) = 1/(3^2) = 1/(3*3) = 1/9
The rule used here is x^(-y) = 1/(x^y) to make the exponent positive.
3^2 turns into 3*3 because the exponent 2 tells us how many copies of the base '3' to multiply out.
Answer: a
Step-by-step explanation: its getting rid of water and the original is 40
She received 12 calls from her son and 30 calls in total.
40% of 30 is 12.