Can someone please solve these, need help ASAP thank you in advance

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

Two lines parallel to a third line are parallel to each other. always sometimes or never

Which expression is equal to (f+g)(x)?