Question 2

(12 pts)

Based on a World Health Organization (WHO) report, the mean hemoglobin level for a population of children is 112 grams/Liter and the standard deviation is 9 grams/Liter. A medical center in the Midwest wants to know if the mean hemoglobin level has decreased, so some research doctors conduct a study of a random sample of 110 children and find that the mean hemoglobin level is 108 grams/Liter with a standard deviation of 11 grams/Liter.

Select the correct answers to these questions:

1. What are the degrees of freedom for the t-distribution of the test statistic?
   109
2. What is the test statistic for this example?
   -3.81
3. Which of the following graphs matches the p-value corresponding to the alternative hypothesis?
   C