Doctors use several kinds of medications to treat the symptomsand complications of COPD; some are taken on a regular basis andothers as needed:

• Bronchodilators. These medications — which usually come in aninhaler — relax the muscles around your airways. Inhaled steroids. Inhaled corticosteroid medications can reduceairway inflammation and help prevent exacerbations. Combination inhalers. Some medications combine bronchodilatorsand inhaled steroids. Salmeterol and fluticasone (Advair) andformoterol and budesonide (Symbicort) are examples of combinationinhalers. So our focus for this question is the Advair Diskus andSymbicort; both maintenance inhalers and often compared. AdvairDiskus may begin working within 30 – 60 minutes and Symbicort maybegin working within 15 minutes, although results may vary in bothcases. We visited the Bowmanville emergency department and monitoredsome of the recently admitted COPD patients who were placed oneither Advair or Symbicort. One-hour after their medication wasdelivered, their SpO2 (peripheral capillary oxygensaturation) levels were recorded; the results were as follows: Theraw and sorted data (smallest to largest) are shown below. SpO2 (%) (Raw data) SpO2 (%) (Sorted Raw Data) Advair Symbicort Advair Combined Symbicort Combined Rank Rank 90 93 88 90 88 90 89 90 90 97 90 93 89 90 90 93 90 93 90 96 96 97 97 97 Medians 90 93 Since it was not decided (hypothesized) which drug would offerthe most benefit after one hour, use the Mann-WhitneyU-Test to test the claim at 95% confidence that thereis a difference in these two products. (Assumethe median SpO2 results from the two drugs aresignificantly different from each other.) State the Null and Alternative Hypothesis (1) State the Decision Rule. (1) Determine U and U’ (4,4) Determine the Test statistic, Utest (1) State your Decision (1)