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Question 1 Given: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 hypothesized memory enhancement of the herbal mix, the now famous drug researcher, Dr. Mindfog, obtains a sample of 15 adult volunteers and has each person take the suggested dosage each day for 4 weeks. At the end of the four-week period, each individual takes a standardized memory test. In the general adult population, the standardized memory test is known to have a mean of = 10, where higher scores demonstrate better performance on the test of memory. The scores for the 15 volunteers are:12, 11, 13, 15, 8, 11, 13, 15, 10, 9, 10, 16, 15, 11, 14With = .01, complete step 4 of the hypothesis testing procedure, what decision and conclusion should the researcher make?A.  The researcher should retain H0 and conclude that there is no correlation between taking the herbs/minerals and actual memory B. The researcher should retain H0 and conclude that taking the herbs/minerals improves memoryC.  The researcher should reject H0 and conclude that there is a positive correlation between taking the herbs/minerals and actual memoryD.  The researcher should reject HA and conclude that taking the herbs/minerals improves memory E. The researcher should reject H0 and conclude that taking the herbs/minerals improves memoryQuestion 2 A researcher is interested in determining the effects of sleep deprivation on the length of time it takes rats to correctly travel a maze to its end point. The researcher wants to know whether the amount of sleep deprivation makes a difference in the speed with which the rats correctly travel the maze. The researcher begins with twenty rats and randomly assigns them to one of two groups such that there are ten rats in each group. One group of 10 rats is sleep deprived for 24 hours prior to performing in the maze, and the second group of 10 rats is sleep deprived for 36 hours before performing in the maze. The researcher records the length of time (in seconds) it takes for each rat to correctly run the maze. The following data were recorded for each rat in each group: Group 1 (24 hour deprivation)          Group 2 (36 hour deprivation) 8                                                            14 10                                                          12 14                                                         16 12                                                          16 9                                                           12 9                                                           16 13                                                        14 8                                                            15 7                                                           10 11                                                        9Is this a one-tailed HA or a two-tailed HA ?A.  one-tailedB.  two-tailedQuestion 3 As the elementary school counselor for six elementary schools in the district, you are interested in developing strategies to aid parent-child interaction on school-related tasks, particularly reading achievement. You believe that positive attention to reading in a non- threatening and non-frustrating home environment for one hour an even will increase reading comprehension scores. A random sample of 12 third-graders reading below grade level were selected to participate in a small “pilot” study. The parents were given instructions on how to engage their child in a “Positive Reading Activities Program” (PRAP) at home, and on how to make this reading activity pleasant and non-frustrating. Parents were also encouraged to provide their child with undivided attention during this reading period for at least one hour per evening. Each child’s reading comprehension scores (high scores indicate better comprehension; 10 is the highest score possible) were assessed with an achievement test the day before and one month after the reading activities program was initiated. The “before” and “after” reading comprehension scores are below for each condition.Child/Family                           Condition 1                               Condition 2  Code                                       “Before PRAP”                        “After PRAP”                                            Comprehension Score              Comprehension Score  a                                                7                                                8 b                                               4                                                 4 c                                                6                                               5 d                                                5                                                6 e                                               4                                                3 f                                               4                                                 7 g                                              3                                                 2 h                                              5                                                 5 i                                                9                                               10 j                                                 8                                                 8 k                                               5                                                 7 l                                                3                                                 4Which hypothesis test needs to be employed here?A.  z test B. one-sample t testC.  dependent t testD.  independent t testE.  Pearson’s rQuestion 4 A psychopharmacologist (a psycholgist interested in the effects of drugs and physiology) is interested in determining the effects of caffeine (from coffee) on exam performance. Twenty students from a large introductory psychology class volunteered to participate in the study; all were dedicated coffee drinkers and all drank caffeinated coffee. The volunteers were then randomly divided into two groups such that there were ten students in each group. One group of 10 students was asked to study the exam material while drinking their normal doses of coffee, and to take the exam while drinking their normal doses of coffee before the test. This group is called the “Coffee with Test” group.The second group of 10 students was asked to study the exam material while drinking their normal doses of coffee, but to take the exam without having consumed coffee for at the least 3 hours beforehand. This group is called the “No-Coffee with Test” group. One student from the “No-Coffee with Test” group became ill and was unable to sit for the exam. The researcher recorded the number of correct responses on the exam. One could get up to 15 items correct on the exam. The scores are below.Coffee with Test                No-Coffee with Test (Number Correct)(Number Correct)                  Group 2Group 1                     8                                               7 10                                             12 14                                             9 12                                            9   9                                             5 9                                              6 13                                          14 8                                               6 12                                             7 11  With = .01, complete step 4 of the hypothesis testing procedure, what decision and conclusion should the researcher make?A. The researcher should reject H0 and conclude that there is a difference in exam performance with no caffiene versus caffiene. B. The researcher should retain H0 and conclude that caffeine has no effect on exam performance C. The researcher should reject HA and conclude that caffeine affects exam performance D. The researcher should reject H0 and conclude that caffeine has no effect on exam performance E. No answer text provided.Question 5 For a population with = 30 and = 8, find the X value that corresponds to z = +0.25.[Round to the nearest hundredths place if a decimal. If your calculated value is not identical to one of the values below, but within plus or minus 0.99 of an answer below, assume it’s a rounding error and select the answer that is closest to your calculated value.] A. X = 21B.  X = 28C.  X = 32D.  X = 39 E. the correct value of X is not listed in alternatives “a” through “d”, even when taking into consideration a rounding error of plus or minus 0.99.Question 6For a population with = 600 and = 100, find the z-score that corresponds to X = 540. [Round to the nearest hundredths place if a decimal. If your calculated value is not identical to one of the values below, but within plus or minus 0.26 of an answer below, assume it’s a rounding error and select the answer that is closest to your calculated value.] A.  z = -1.04 B. z = -.60 C. z = .70D.  z = 1.75E.  the correct value of z is not listed in alternatives “a” through “d”, even when taking into consideration a rounding error of plus or minus 0.26.Question 7 A researcher is interested in determining the effects of sleep deprivation on the length of time it takes rats to correctly travel a maze to its end point. The researcher wants to know whether the amount of sleep deprivation makes a difference in the speed with which the rats correctly travel the maze. The researcher begins with twenty rats and randomly assigns them to one of two groups such that there are ten rats in each group. One group of 10 rats is sleep deprived for 24 hours prior to performing in the maze, and the second group of 10 rats is sleep deprived for 36 hours before performing in the maze. The researcher records the length of time (in seconds) it takes for each rat to correctly run the maze. The following data were recorded for each rat in each group: Group 1 (24 hour deprivation)         Group 2 (36 hour deprivation) 8                                                            14 10                                                         12 14                                                         16 12                                                         16 9                                                          12 9                                                          16 13                                                        14 8                                                         15 7                                                          10 11                                                         9Which of the following are the correct statements of the null and alternate hypotheses, H0 and HA ?A. H0: µ1 = µ2 and HA: µ1 µ2B.  H0: µ1 µ2 and HA: µ1 = µ2C.  H0: µ1 > µ2 and HA: µ1 µ2D.  H0: µ1 µ2 and HA: µ1 > µ2E.  H0: µ1 < µ2 and HA: µ1 µ2 F. H0: µ1> µ2 and HA: µ1 < µ2 G. H0: p >0 and HA: < 0H.  H0: p<0 and HA: > 0I.  H0: P= 0 and HA: 0