Letxbe a random variable that represents the pH of arterial plasma (i.e., acidity of the blood). For healthy adults, the mean of thexdistribution is= 7.4.A new drug for arthritis has been developed. However, it is thought that this drug may change blood pH. A random sample of41patients with arthritis took the drug for 3 months. Blood tests showed thatx=8.6with sample standard deviations=3.2.Use a 5% level of significance to test the claim that the drug has changed (either way) the mean pH level of the blood.(a) What is the level of significance?

State the null and alternate hypotheses.

H₀:= 7.4;H₁:< 7.4H₀:7.4;H₁:= 7.4H₀:= 7.4;H₁:> 7.4H₀:> 7.4;H₁:= 7.4H₀:= 7.4;H₁:7.4

(b) What sampling distribution will you use? Explain the rationale for your choice of sampling distribution.

The Student'st, since the sample size is large andis known.The Student'st, since the sample size is large andis unknown.The standard normal, since the sample size is large andis known.The standard normal, since the sample size is large andis unknown.

What is the value of the sample test statistic? (Round your answer to three decimal places.)

(c) Find theP-value. (Round your answer to four decimal places.)