4. [-/4.08 Points] DETAILS BBUNDERSTAT12 8.2.012.MI.S. MY NOTES ASK YOUR TEACHER Let x be a random variable that represents the pH of arterial plasma (I.e., acidity of the blood). For healthy adults, the mean of the x distribution is , = 7.4. A new drug for arthritis has been developed. However, It is thought that this drug may way) the mean pH level of the blood. change blood pH. A random sample of 36 patients with arthritis took the drug for 3 months. Blood tests showed that x = 8.6 with sample standard deviation s = 3.3. Use a 5% level of significance to test the claim that the drug has changed (either LA USE SALT (a) What is the level of significance? State the null and alternate hypotheses. HO: M > 7.4; H1: 1 = 7.4 HO: H = 7.4; H1: H 7.4 (b) What sampling distribution will you use? Explain the rationale for your choice of sampling distribution. The standard normal, since the sample size is large and a is unknown. The Student's t, since the sample size is large and a is known. The standard normal, since the sample size is large and a is known. The Student's t, since the sample size is large and a is unknown. What is the value of the sample test statistic? (Round your answer to three decimal places.) (c) Estimate the P-value. P-value > 0.150 0.100