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Select all that are true.

For this question, enter your final answer here in the Canvas exam.  You may show your work here or on scratch paper. Label each part of the question clearly.  If showing work on scratch paper, submit a photo of the work in the designated area in Canvas within 5 minutes of completing the exam.  Researchers conducted a study to determine whether meditation may help the body respond to stressful situations.  In the study, people with anxiety disorder were randomly assigned to one of two groups: one group took an eight-week course in mindfulness meditation, in which they learned to focus on the present moment and accept difficult thoughts or feelings.  The other group took a course in stress management that did not involve meditation.  For each group, the researchers measured participants’ levels of stress hormones (measured in pg/mL) during a stressful event, compared with how their bodies reacted before the course.  A partial analysis of the results follows: Group n Sample Mean Std Dev Meditation improvement 80 10 20 Stress Management improvement 80 -5 25 df 150.7 Difference in mean improvement: (Meditation – Stress Management) 15 95% Confidence Interval (7.928, 22.07)   a. [4] Interpret the confidence interval estimate in the context of this scenario. b. [2] Based on the confidence interval in part a, is the difference in mean improvement in stress hormone levels between the two groups significantly different? Explain.

A new program claims that it decreases the hours of in-school suspension for at-risk middle school students. A small study using 10 students found a statistically significant decrease. If, in fact, the mean in-school suspension hours is not decreased by this program, this study’s conclusion is an instance of

It can be assumed that men have a mean hemoglobin level (Hb) of 15.50 g/dL with standard deviation 1.07 g/dL and that hemoglobin levels are normally distributed. A lab is testing some new equipment for measuring blood samples, and using the Hb levels for six men, constructed a 98% confidence interval  (14.03, 16.97). Use this information to fill in the blanks below.    The margin of error in this confidence interval is  

A study measured various cardiovascular risk factors in children at birth.  One item of interest was to determine if heart rates differ, on average, between Caucasian and African American newborns.  What statistical inference technique should be used?

An engineer has developed a new process that showed significant increase in the breaking strength of steel beams used in the construction of buildings.  You read the study report and find a 95% confidence interval estimate for the mean increase in breaking strength to be between 0.01 and 0.05 pound.  These results are 

In a pharmaceutical manufacturing facility, tablets are produced to contain an average weight of 500 mg with minimal variation to ensure consistent dosage. However, due to slight inconsistencies in the production process, the weight of tablets is expected to follow a normal distribution. To estimate the true mean weight of the tablets, five independent samples are selected from different batches on separate days and weighed. Which statistical inference procedure should be performed with the resulting data?

Sales representatives at a large local logistics company receive commission pay each month in addition to their monthly base pay. A random sample of 65 sales representatives at this company is selected. The sample mean monthly commission pay was $3,451 and the standard deviation was $289. The 90% confidence interval estimate for the true mean monthly commission pay for sales representatives at this logistics company is between $[a] (lower bound) and $[b] (upper bound). Round your answer to two decimal places.

When Cheetos Crunchy Buffalo was introduced as part of the Frito-Lay product line, the company most likely used what type of distribution?

Which of the following best characterizes multichannel distribution?