.... I need Correct answers only

4. Which of the following are true statements? I. If there is sufficient evidence to reject a null hypothesis at the 10% level, then there is sufficient evidence to reject it at the 5% level. II. Whether to use a one- or two-sided test is typically decided after the data are gathered. III. If a hypothesis test is conducted at the 1% level, there is a 1% chance of rejecting the null hypothesis. (A) I only (B) II only (C) III only (D) I, II, and III (E) None are true. 5. A manufacturer claims that a particular automobile model will get 50 miles per gallon on the highway. The researchers at a consumer-oriented magazine believe that this claim is high and plan a test with a simple ramdom sample of 30 cars. Assuming the standard deviation between individual cars is 2.3 miles per gallon, what should the researchers conclude if the sample mean is 49 miles per gallon? (A) There is not sufficient evidence to reject the manufacturer's claim; 49 miles per gallon is too close to the claimed 50 miles per gallon. (B) The manufacturer's claim should not be rejected because the P-value of .0087 is too small. (C) The manufacturer's claim should be rejected because the sample mean is less than the claimed mean. (D) The P-value of .0087 is sufficient evidence to reject the manufacturer's claim. (E) The P-value of .0087 is sufficient evidence to prove that the manufacturer's claim is false. 6. A historian believes that the average height of soldiers in World War II was greater than that of soldiers in World War I. She examines a random sample of records of 100 men in each war and notes standard deviations of 2.5 and 2.3 inches in World War I and World War II, respectively. If the average height from the sample of World War II soldiers is 1 inch greater than from the sample of World War I soldiers, what conclusion is justified from a two-sample hypothesis test where Ho : #1 - /2 = 0 and H. : #1 - #2