You measure 31 dogs' weights, and find they have a mean weight of 39 ounces. Assume the population standard deviation is 13.1 ounces. Based on this, construct a 99% confidence interval for the true population mean dog weight.

The point a is at –2 and the point b is at 7. marissa would like to divide this line segment in a 4: 3 ratio, and she would like to use the formula x = (x2 – x1) + x1. what values should she substitute into the formula? a = a + b = x1 = x2 =