A researcher studied the effects of pancuronium-induced muscle relaxation on circulating plasma ...

A researcher studied the effects of pancuronium-induced muscle relaxation on circulating plasma volume on newborn infants weighing more than 1700 grams who required respiratory assistance within the first 24 hours of birth and met other clinical criteria. The following table is a result of measurements of plasma volume (ml) made during mechanical ventilation.
Subject group Sample Size sample mean Sample SD
paralyzed 5 48.0 8.1
non-paralyzed 7 56.7 8.1
a. You may assume equal standard deviations. Construct a 98% confidence interval for the difference of the two population means
b. What are your conclusions? Do you think there is a difference between the two population means?