What is the answer for a+(-5)-12

Asimple random sample of size nequals14 is drawn from a population that is normally distributed. the sample mean is found to be x overbar equals 70 and the sample standard deviation is found to be sequals13. construct a 90% confidence interval about the population mean

(hurry! ) which expression is equivalent to the following complex fraction?

Write an equation of the line that passes through 9,2 and is parallel to the line y=5/3x+9