Question: A study of 13 children with asthma compared single inhaled doses of formoterol (F) and salbutamol (S). The outcome measured was the child’s peak expiratory flow (PEF)

eight hours after treatment.

Let mu denote the population mean of the difference between the PEF values for the F and S treatments. Perform a significance test for the null hyp. that mu = 0 against the two-sided alternative. Give a 95% confidence interval for mu.