The effectiveness of a new bug repellent is tested on 25 subjects for a 10 hour period. (Assume normally distributed population.) Based on the number and location of the bug bites, the percentage of surface area exposed protected from bites was calculated for each of the subjects. The results were as follows: ?⎯⎯⎯=93,  ?=12  The new repellent is considered effective if it provides a percent repellency of at least 91. Using ?=0.05, construct a hypothesis test with null hypothesis ?=91 and alternate hypothesis ?>91 to determine whether the mean repellency of the new bug repellent is greater than 91 by computing the following: (a)    the degrees of freedom     (b)    the test statistic       The final conclusion is A. We can reject the null hypothesis that ?=91. Our results indicate that the new bug repellent is effective. B. There is not sufficient evidence to reject the null hypothesis that ?=9. Our results do not provide enough evidence that the new bug repellent is effective.

A researcher is interested in determining if sleeping more hours the night before an exam will improve student math practice test scores. She randomly divides the class into two groups. One group is instructed to sleep 9 hours. The other group is instructed to sleep 6 hours. Students were asked to complete a practice math test the following day. The researcher then compares the average test score of each group. What is the DV? O the class O the researcher average test score O sleep (9 hours vs 7 hours)

For a population with m = 62 and s = 12, find the X value that corresponds to each of the following z-scores: -0.25, -1.50, 0.50, 2.00

In a survey, the sample consisted of 1087 adults who were parents of school-aged children. The sample was selected in a way that makes it reasonable to regard it as representative of the population of parents of school-aged children. One question on the survey asked respondents how much time (in hours) per month they spent volunteering at their children's school during the previous school year. The following summary statistics for time volunteered per month are given below. n = 1087 x = 5.5 median = 1

Given SST = 2415, SSE = 1725, n = 7, and k = 2, calculate the value of the overall F test statistic. O Feal = 3.50 O Fcal = 1.25 O Fcal = 0.40 O Fcal = 0.80

Scientists have discovered a new bird species; however, they only found 15 birds of such species. They measured the height (in cm) of these 10 birds:12.94,  5.80, 15.47, 14.14, 7.48, 9.21,  9.79,  8.86, 17.75, 10.39. I entered the data into R as shown below: bird <- c(12.94,  5.80, 15.47, 14.14, 7.48, 9.21,  9.79,  8.86, 17.75, 10.39) Treat this data as population data. Which of the following R code computes the variance of the height of the birds?   A. var(bird) B. sum((bird - mean(bird))^2)/length(bird) C. mean((bird - mean(bird))^2) D. sum((bird - mean(bird))^2)/9 E. B and C F. A and D G. B and D H. A and C

Please solve for G, H, and I

he level of cretaine phosphokinase (CPK) in blood samples measures the amount of muscle damage for athletes. At Jock State University, the level of CPK was determined for each of 25 football players and 15 soccer players before and after practice. The two groups of athletes are trained independently. The data summary is as follows :   For football players: Data for Football players n=25 Before Practice After Practice Difference (Before-After) Mean 254.73 225.6 29.13 Standard deviation 115.5 132.6 21.00   For soccer players: Data for Soccer players n=15 Before Practice After Practice Difference (Before-After) Mean 177.1 173.8 3.3 Standard deviation 60.7 64.4 6.88   Assume that all the data above are normal  Test the claim that the mean CPK level has DECREASED for soccer players AFTER exercise (compared to the mean BEFORE exercise), using α=0.10.  AFTER practice, do football players have a DIFFERENT mean CPK values compared to soccer players? Test this claim by…

Health care workers who use latex gloves with glove powder on a daily basis are particularly susceptible to developing a latex allergy. Each in a sample of 44 hospital employees who were diagnosed with a latex allergy based on a skin-prick test reported on their exposure to latex gloves. Summary statistics for the number of latex gloves used per week are x= 19.4 and s = 11.7. Complete parts (a) - (d). a. Give a point estimate for the average number of latex gloves used per week by all health care workers with a latex allergy. b. Form a 95% confidence interval for the average number of latex gloves used per week by all health care workers with a latex allergy. (Use integers or decimals for any numbers in the expression. Round to two decimal places as needed.) c. Give a practical interpretation of the interval, part (b). O A. One can be 95% confident that latex gloves cause allergies for all who use a number of gloves contained in the interval. O B. One can be 95% confident that the…

In a survey, the sample consisted of 1087 adults who were parents of school-aged children. The sample was selected in a way that makes it reasonable to regard it as representative of the population of parents of school-aged children. One question on the survey asked respondents how much time (in hours) per month they spent volunteering at their children's school during the previous school year. The following summary statistics for time volunteered per month are given below. n = 1087 x = 5.5 median = 1 In USE SALT (a) What does the fact that the mean is so much larger than the median tell you about the distribution of time spent volunteering per month? The fact that the mean is much greater than the median suggests that the distribution of times spent volunteering in the sample was negatively skewed. The fact that the mean is much less than the median suggests that the distribution of times spent volunteering in the sample was positively skewed. The fact that the mean is much greater…