PLS help i've been trying this for an hour i still don't get it

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

Adj has a total of 1075 dance and rock songs on her system. the dance selection is 4 times the size of the rock selection. write a system of equations to represent the situation.

Of f(x) is byof f(x)=-3|x| x-.f(x)? a )f(x)=3|x| b) f(x)=|x+3| c) f(x)= -3|x| d) f(x)= -|x+3|