1. Strategic placement of lobster traps is one of the keys for a successful lobster fisherman. A study was conducted of the average distance separating trapscalled trap spacingdeployed by lobster fishermen. The trap-spacing measurements (in meters) for a sample of seven teams from fishing cooperative A, and a sample of eight teams from fishing cooperative B are repeated in the accompanying table. For this problem, we are interested in comparing the mean trap-spacing measurements of the two fishing cooperatives. (Since the sample from fishing cooperative A is listed first, treat it as the first sample.

Table;

A Cooperative:	90	90	72	84	74	88	70
B Cooperative:	98	118	150	129	89	83	74	82

Compute a point estimate of the target parameter.

B) The point estimate __

D) Find a 90% confidence interval for the target parameter. Assume 21=22. The confidence interval is

4) Is the probability of a bowler rolling a strike higher after he has thrown four consecutive strikes? Researchers investigated the phenomenon of a "hot hand" in bowling. Frame-by-frame results were collected on 43 professional bowlers. For each bowler, the researchers calculated the proportion of strikes rolled after bowling four consecutive strikes and the proportion after bowling four consecutive nonstrikes. The data on 4 of the 43 bowlers are shown in the accompanying table.

Bowler	Proportion of Strikes
After Four Strikes	After Four Nonstrikes
1	0.684	0.400
2	0.632	0.421
3	0.683	0.431
4	0.610

Find the test statistic for this test. Select the correct choice below and fill in the answer box within your choice.

a) T=

b) T_=

c) T+=

7)

Counselors at a summer camp for overweight and obese adolescents develop a weight-management program for each camper that centers on nutrition education and physical activity. In a recent study, the body mass index (BMI) was measured for each of

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campers both at the start and end of camp. Summary statistics on BMI measurements are shown in the table to the right.

		Mean	Standard Deviation
	Starting BMI	34.7	5.9
	Ending BMI	30.8	5.5
	Paired Differences	03.9	1.8

Give the null and alternative hypotheses for determining whether the mean BMI at the end of camp is less than the mean BMI at the start of camp.

Let 1 be the population mean BMI at the start of camp, 2 be the population mean BMI at the end of camp, and d=12.

H0:d ( ,>,<,= )enter your response here

Ha:d( ,>,<,= ) enter your response here

c)

Calculate the test statistic using the formula for an independent-samples t-test.

t=

d)

Calculate the test statistic using the formula for paired-difference t-test.

t=

H).

Find a 99% confidence interval for the true mean change in BMI for the campers.

The 99% confidence interval is ( , )