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 of31patients with arthritis took the drug for 3 months. Blood tests showed thatx=8.6with sample standard deviations=3.1.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. (Enter != foras needed.)

H₀:

H₁:

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

We'll use the Student'st, since the sample size is large andis known.

We'll use the Student'st, since the sample size is large andis unknown.

We'll use the standard normal, since the sample size is large andis known.

We'll use the standard normal, since the sample size is large andis unknown.

Compute the appropriate sampling distribution value of the sample test statistic. (Round your answer to two decimal places.)

(c)Estimate theP-value:

.P-value > 0.150

0.100 <P-value < 0.150

0.050 <P-value < 0.100

0.020 <P-value < 0.050

P-value < 0.020

Based on your answers in parts (a) to (c), will you reject or fail to reject the null hypothesis? Are the data statistically significant at level ?

At the = 0.05 level, we reject the null hypothesis and conclude the data are statistically significant.

At the = 0.05 level, we reject the null hypothesis and conclude the data are not statistically significant.

At the = 0.05 level, we fail to reject the null hypothesis and conclude the data are statistically significant.

At the = 0.05 level, we fail to reject the null hypothesis and conclude the data are not statistically significant.

(e)Interpret your conclusion in the context of the application.

There is sufficient evidence at the 0.05 level to conclude that the drug has changed the mean pH level of the blood.

There is insufficient evidence at the 0.05 level to conclude that the drug has changed the mean pH level of the blood.