PLEASE HELP!!!!!

1.

(06.05 LC) You want to find whether there is a difference in the proportion of male and female college students who had a job during the past semester. Out of a simple random sample of 200 female and 250 male college students, you find that 146 females and 212 males reported they had a job the previous semester. Which hypotheses should you test if p_mand p_fdenote the proportions of all college males and females, respectively, who worked the previous semester? (5 points)

	H0: pm pf= 0 versus Ha: pm pf 0
	H0: pm pf= 0 versus Ha: pm pf> 0
	H0: pm pf= 0 versus Ha: pm pf
	H0: pm pf> 0 versus Ha: pm pf= 0
	H0: pm pf 0 versus Ha: pm pf= 0

2.

(06.02 MC) An individual is arrested for stealing and pleads not guilty at trial. The jury can only find him guilty if there is evidence beyond a reasonable doubt to reject the assumption of innocence. Describe what could occur if the jury makes a Type I error? (4 points)

	The jury finds the individual innocent and he is released from jail, but he is actually guilty.
	The jury finds the individual guilty, he is put in jail, and he is actually guilty.
	The jury finds the individual innocent, he is released from jail, and he is actually innocent.
	The jury finds the individual guilty and he is put in jail, but he is actually innocent.
	A conclusion cannot be made based on the information given.

3.

(06.05 MC) A researcher wants to conduct a study to determine whether a newly developed antibullying program is successful. Two randomly selected groups of 50 students each, identified as control and treatment groups, are formed from 100 students accused of bullying in a particular school district. Both groups receive a set of antibullying reading materials and a lecture from a teacher and a bully victim about the dangers of bullying. In addition, the treatment group also receives materials from the newly developed program. Twenty-four of the 50 students in the control and 31 of the 50 students in the treatment group are reported to no longer bully others one year later. Use the results to test the hypotheses H₀: p₁= p₂and H_a: p₁ p₂where p₁represents the proportion of students who succeed in the control program and p₂represents the proportion of students who succeed in the newly developed program. What can you conclude using the significance level = 0.05? (5 points)

	The results of the new bullying program are not significantly different than the control program at reducing bullying because the p-value is greater than = 0.05.
	The new bullying program is effective at reducing bullying because the proportion of students who no longer bully others is greater in the treatment group than control group.
	The results of the new bullying program are significantly different than the control program at reducing bullying because the p-value is greater than = 0.05.
	The new bullying program is not significantly different than the control program at reducing bullying because the difference in the proportions of the control group and treatment group is small.
	The new bullying program is effective at reducing bullying because the standard deviation is small, 0.0990.

4.

(06.05 MC) The way in which response options are presented in a question can affect a person's response. Two hundred randomly selected people were asked about their milk chocolate or dark chocolate preference. One hundred of the participants were randomly given the option of milk chocolate first and the remaining 100 participants were given the option of dark chocolate first. The results are given in the table.

To conclude if the order in which options are presented in a question affects the answer, a two-proportion z-test was conducted. What is the correct p-value of the test? (4 points)

	0.0594
	0.1189
	0.3193
	0.4650
	0.5200

5.

(06.01 LC) An opinion poll asked a random sample of adults whether they believe flu shots are ineffective in the United States. A commentator believes less than 35% of all adults believe they are ineffective. Which null and alternative hypotheses should be used to test this claim? (4 points)

	H0: p 0.35, Ha: p
	H0: p = 0.35, Ha: p
	H0: p = 0.35, Ha: p 0.35
	H0: p a: p = 0.35
	H0: p = 0.35, Ha: p > 0.35

6.

(06.01 MC) A student performs a test of H₀: p = 0.4 versus H_a: p 0.4 and gets a p-value of 0.03. The student writes: "Because the p-value is not equal to 0.4, we reject the null hypothesis." What is wrong with the student's conclusion? (4 points)

	The p-value should be compared with a significance level such as = 0.05, not the hypothesized value of p.
	The p-value should be compared with the mean, not the hypothesized value of p.
	The p-value should be compared with the standard deviation, not the hypothesized value of p.
	The student should have stated the data prove Hais true.
	The student should have stated the data prove H0is true.

7.

(06.02 LC) In a test of the hypothesis H₀: p = 0.8 against H_a: p > 0.8, the power of the test when p = 0.9 is greatest for which of the following? (4 points)

	n = 75, = 0.05
	n = 75, = 0.10
	n = 70, = 0.10
	n = 70, = 0.05
	There is not enough information given to draw a conclusion.

8.

(06.05 MC) Which of the following is a TRUE statement about hypothesis testing? (4 points)

	Whether to use a one-sided or a two-sided test is typically decided after the data are gathered.
	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.
	If a hypothesis test is conducted at the 1% level, there is a 1% chance of rejecting the null hypothesis.
	The power of a test concerns its ability to detect an alternative hypothesis.
	The probability of a Type I error plus the probability of a Type II error always equals one.

9.

(06.04 MC) A poll of 1,000 randomly selected registered voters was taken and 680 responded that they favor candidate X for mayor (p₁= 0.6800). Just before the election, another poll of 900 registered voters was taken and 598 individuals responded that they favor candidate X (p₂= 0.6644). A 90% two-proportion z confidence interval for the true difference betweenp₁andp₂was found to be (-0.0199, 0.0510). What is the meaning of the interval in the context of the problem? (4 points)

	There has been no change in support for the candidate.
	There has been a substantial drop in support for the candidate.
	There has been a substantial gain in support for the candidate.
	It is probable for the candidate to get most of the votes because the confidence interval includes zero.
	It is not probable for the candidate to get most of the votes because support has dropped below 50%.

10.

(06.04 LC) A recent study states that high winds can affect the pollination rate of sunflowers. It reported that 52 of 60 sunflower plants that were shielded from high winds pollinated and 41 of 55 sunflower plants left unshielded were pollinated. Choose the 98% confidence interval that represents the difference between the proportions of shielded and unshielded sunflower plants that are pollinated. (4 points)

O 52 93 93 + 2.326, + 81 55 115 115 60 55 O 52 41 93 93 1 60 55 + 2.576. + 115 115 60 55 O 52 93 93 52 41 + 2.326. 55 V 715 715 + = 60 60 55 O 52 52 41 41 41 60 60 55 55 + 55 +2.3261 60 55 O 52 52 41 41 1- 1- 3 41 60 60 55 55 + 2.5761 55 60 55