Adrenomedullin, a hormone found in the adrenal gland, participates in bloodpressure and heart-rate control. The level of adrenomedullin is raised in a variety of diseases, and medical complications, including recurrent pregnancy loss, can result. In an article by M. Nakatsuka et al. titled "Increased Plasma Adrenomedullin in WomenWith Recurrent Pregnancy Loss" (Obstetrics & Gynecology, Vol. 102, No. 2, pp. 319-324), the plasma levels of adrenomedullin for 38 women with recurrent pregnancy loss had a mean of 5.6 pmol/L and a sample standard deviation of 1.9 pmol/L, where pmol/L is an abbreviation of picomoles per liter.
a. Find a 90% confidence interval for the mean plasma level of adrenomedullin for all women with recurrent pregnancy loss.
b. Interpret your answer from part (a).