PLEASE HELP I JUST NEED 5,6,7 and 8 done <3

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

What are the solutions of the equation? z^2 + 11z + 24 = 0 a. 8, -3 b. 8, 3 c. -8, -3 d. -8, 3

You eat $0.85 for every cup of hot chocolate you sell. how many cups do you need to sell to earn $55.25