Please help with my statistics practice questions ASAP.

Reque A nutrition store in the mall is selling "Memory Booster," which is a concoction of herbs and minerals that is intended to improve memory performance. To test the effectiveness of the herbal mix, a researcher obtains a sample of n = 16 people and asks each person to take the suggested dosage each day for four weeks. This researcher is interested in whether the herbal supplement has any effect, positive or negative. At the end of the four-week period, each individual takes a standardized memory test. The scores from the sample produce a mean of X = 26 with SS = 960. In the general population, the standardized test is known to have a mean of J = 20 1. What value would he use as his standard error (or estimated standard error)? a) 64 b) 60 c) 2 d) 2.07 e) 1.94 2. What is the value of the appropriate test statistic for this experiment? a) 0.75 b) 0.77 c) 2.90 d) 3.00 e) 3.10 3. For alpha = .05, what is the critical value of the appropriate test statistic? a) +/-1.753 bl + /- 2131 NOW 12 WE X MacBook Air 888 F4 FS F6 P7 F812022 7 40 9 Rec c) 2.90 d) 3.00 e) 3.10 3. For alpha = .05, what is the critical value of the appropriate test statistic? a) +/-1.753 b) +/- 2.131 c) +/-2.120 d) +/-1.746 e) +/-1.96 4. Given the test statistics and critical values you found above, the researcher... a) should fail to reject the null hypothesis b) should reject the null hypothesis c) should conclude that the sample mean he obtained was unlikely to happen due to chance alone if there was no effect of treatment d) both A and B e) both B and C 12 W X MacBook Air F4 F5 44 F6 F7 F8 FO112022 * 4 0 6 Reque Dr. Gold N. Tanner visits Pacific Beach often and is convinced that the water is colder than usual whenever he decides to go. Dr. Tanner starts to record the temperature of the water every time he goes to the beach. After a bit of research, he learns that the daily ocean water temperature at Pacific Beach is normally distributed with a mean of 65 and a standard deviation of 4. The mean temperature for the 25 days he goes to the beach is 67. Help him answer the following two questions. 5. What value would he use as the standard error (or estimated standard error) in the denominator of his test statistic? a) 0.16 b) 0.80 c) 4 d) 12.50 e) 65 6. What is Dr. Tanner's observed test statistic? a) +2.50 b) -0.50 c) -2.50 d) -12.5 e) +0.50 7. Which of the following most precisely describes what ( the standard error of X ) measures ? 127 12 W X MacBook Air 888 FA F5 14 F6 F7 P8 FOall2022 * 4 0 6 Reque 7. Which of the following most precisely describes what OF (the standard error of X ) measures? a) The standard amount that scores in the population will vary around the population mean b) The standard amount scores in a sample will vary around the sample mean c) The standard amount means of samples will vary around the population mean d) How far a specific sample was from the population mean 8. The distribution of sample means: a) Is always normally distributed b) Is normally distributed only if the original population is normally distributed c) Is normally distributed only if the sample is normally distributed d) Is normally distributed only if the sample size is greater than about 35 e) Is normally distributed if the original population is normally distributed OR if the sample size is large enough (n > ~30) 12 W IIIII X MacBook Air BU FS 868 F4 FS F79. A single sample t-test should be used instead of a z-test when: a) The population mean is not known b) The sample mean is not known c) The population standard deviation is known d) The population standard deviation is not known e) None of the above For the following four questions, assume that a researcher is interested in finding out what substances can affect exam scores. For this experiment, the researcher is specifically interested in whether eating ice cream before an exam changes students' exam scores and plans to use a two-tailed, non-directional hypothesis test. He knows that the average score for students on a particular exam is 83%. He gives ice cream cones to 15 randomly selected students before the exam and finds that his sample has a mean of 86% and the sample standard deviation is 5%. 10. Which of the following should the researcher perform? a) A z-score calculation b) A one sample z-test c) one sample t-test d) independent samples t-test e) Cohen's d test 11. How many degrees of freedom does this test have? a) 16 b) 15 c) 14 d) 30 e) This test does not utilize degrees of freedom 12 TO WE X MacBook Air 868 F4 FS F6 F7 F8 FO\fallzy Request edit a 14. Phoney Wireless is trying to get into the text messaging business and wants to determine whether UCSD students send text messages at a different rate than the general public. The average number of texts per day sent by young adults in the United States is 18, with o = 5. A random sample of 25 UCSD students finds that students at UCSD send an average of 20 texts per day. What is the observed value of the appropriate test statistic for this study? a) 4.47 b) -2.5 c) 0.4 d) 10 e) 2.0 15. Under which circumstances is it most likely to get a sample with an extreme t-statistic? a) With a sample of n =3 b) With a sample of n > ~30 c) With a sample of n = 100 d) When n approaches infinity e) The likelihood of getting an extreme t-statistic does not depend on sample size 16. Which of the following is an example of a type I error? a) Your 'check engine' light turns on, but your engine is actually fine b) Your 'check engine light turns on, and there is something wrong with your engine c) Your 'check engine light does not turn on, but there is something wrong with your engine d) You're check engine light does not turn on, and there is nothing wrong with your engine e) None of the above 17. When you increase your sample size, the standard error: a) Increases b) Decreases cl Stowe thec 15 12 X zoom MacBook Air 858 FA F5 F6 F7 3 E R T Y O17. When you increase your sample size, the standard error: a) Increases b) Decreases c) Stays the same d) It depends on whether the original population is normally distributed or not e) None of the above COGS 14B Midterm 2 Fall 2022 18. . Which of the following is the correct interpretation of the following statement about a hypothesis test: "A statistically significant effect of drug A was found, p <.05 a there is less than change that the nulle effect true b chance alternative hypothesis c of getting observed or one more extreme if null d e both and statistical power is: now w x macbook air fa fs f6 e7 fb sk r y o>