DDT is a pesticide banned in the United States for its dange

DDT is a pesticide banned in the United States for its danger to humans and animals. In an experiment on the impact of DDT, 6 rats were exposed to DDT poisoning and 6 rats were not. For each rat in the experiment, a measurement of nerve sensitivity was recorded. The researchers suspected that the mean nerve sensitivity for rats exposed to DDT is greater than that for rats not poisoned. The data follow:

      Poisoned rats:        12.207 16.869 25.050 22.429 8.456   20.589

      Unpoisoned rats:    11.074 9.686 12.064 9.351   8.182   6.642

Let ?1 be the mean nerve sensitivity for rats poisoned with DDT. Let ?2 be the mean nerve sensitivity for rats not poisoned with DDT.

Which of the following is the alternative hypothesis for the relevant significance testing problem?

A.

H_a: u1> u2

B.

H_a: x1 =/ x2

C.

H_a: u1< u2

H_a: u1 =/ u2

Solution

Which of the following is the alternative hypothesis for the relevant significance testing problem?

A. H_a: u1 > u2

B. H_a: x1 =/ x2

C. H_a: u1< u2

D.

H_a: u1 =/ u2

Given: researchers suspected that the mean nerve sensitivity for rats exposed to DDT is greater than that for rats not poisoned.

The answer : A