# Complete the following exercises located at the end of each chapter and put them into a Word document to be submitted as directed by the instructor.

#### Complete the following exercises located at the end of each chapter and put them into a Word document to be submitted as directed by the instructor.

Show all relevant work; use the equation editor in Microsoft Word when necessary.

1. Chapter 13, numbers 13.6, 13.8, 13.9, and 13.10

2. Chapter 14, numbers 14.11, 14.12, and 14.14

3. Chapter 15, numbers 15.7, 15.8, 15.10 and 15.14

13.6 It’s well established, we’ll assume, that lab rats require an average of 32 trials in a complex water maze before reaching a learning criterion of three consecutive errorless trials. To determine whether a mildly adverse stimulus has any effect on performance, a sample of seven lab rats were given a mild electrical shock just before each trial.

(a) Given that X 5 34.89 and s 5 3.02, test the null hypothesis with t , using the .05 level of signiﬁ cance.

(b) Construct a 95 percent conﬁdence interval for the true number of trials required to learn the water maze. (c) Interpret this conﬁdence interval.

13.8 Assume that on average, healthy young adults dream 90 minutes each night, as inferred from a number of measures, including rapid eye move-ment (REM) sleep. An investigator wishes to determine whether drinking coffee just before going to sleep affects the amount of dream time. After drinking a standard amount of coffee, dream time is monitored for each of 28 healthy young adults in a random sample. Results show a sample mean, X, of 88 minutes and a sample standard deviation, s , of 9 minutes.

(a) Use t to test the null hypothesis at the .05 level of signiﬁ cance.

(b) If appropriate (because the null hypothesis has been rejected), construct a 95 percent conﬁ dence interval and interpret this interval.

13.9 In the gas