The product of negative two of number decreased by six is ten

Which expression is equivalent to (3^2)^-2 a.-81 b.-12 c.1/81 d.1/12

The weight of full–grown tomatoes at a farm is modeled by a normal distribution with a standard deviation of 18.4 grams. the 95 percent confidence interval for the mean weight of the tomatoes is calculated using a sample of 100 tomatoes. what is the margin of error (half the width of the confidence interval)?

In the xy-plane, if the parabola with equation passes through the point (-1, -1), which of the following must be true?