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A report from 2026 clained 22% of Americans over the age of 5 speak more than one language. It is believed that the actual percentage is lower than this. In a random sample of 244 Americans over the age of 5, 47 spoke more than one language. Determine the value of test statistic and p-value associate with this test. (Round both to three decimal places.) test statistic = [z] p-value = [p]

Excessive muscle mass or adipose tissue may limit flexibility primarily by: 

Why might women generally exhibit greater flexibility than men?

Which characteristics apply to dynamic stretching? (Select all that apply.)

Which factor MOST directly links flexibility training to reduced low back pain?

Holding each stretch for 30 seconds across 3 repetitions MOST directly addresses which FITT-VP component? 

Which muscles are considered part of the core for spinal stability? (Select all that apply.) 

Static stretching is MOST appropriately performed:

On stat key in the appropriate randomization hypothesis test section you can find a data set titled “ADHD Diagnosis (high social media vs. low)”.  This data set is based on a study where teens who showed no ADHD symptoms were tracked over a few years and researchers noted whether or not each teen was later diagnosed with ADHD. Complete the steps below to perform a randomization hypothesis test on stat key (lock5stat.com) to determine if at the 5% significance level there is enough evidence to conclude the population proportion of ADHD diagnoses is higher for teens with high social media use. Blank 1/Part 1:  Write the hypotheses.  On your scrap sheet label this problem 4 blank 1 and use good notation to write the hypotheses.  For the online test you can just type in a sentence saying what the alternative hypothesis would be. Blank 2/Part 2:  Find the data set and use stat key to make the randomization dotplot giving the p-value.  Include a sketch on your work sheet and just give the p-value online here. Blank 3/Part 3: Write your conclusion in context.  (only part credit for a statement about whether not to reject the null hypothesis)

An online clothing company has historically had to process exchanges for 22% of online orders due to customers choosing the incorrect size.  They developed an online size guide to try to lower this proportion.  Before launching the size guide fully, the company tries the size guide for a sample of orders so they can do a hypothesis test at the 5% significance level to see if the size guide will lower the population proportion of orders needing an exchange. Blank/Part 1:  Write the hypotheses.  Online you can just type in a sentence but on your work sheet, label this problem 3 and write the hypotheses using good notation. Blank/Part 2:  Of the listed sample proportions below, which would provide the STRONGEST evidence against the null and in support of the alternative hypothesis?  (answer a, b or c) a) 0.27            b)  0.20             c)  0.18             d) 0.06 Blank/Part 3:  If the p-value came out to be 0.018, which choice below (a, b, or c) has the correct conclusion in context. a) Reject the null hypothesis.  At the 5% significance level there is enough evidence to conclude the size guide will lower the population proportion of orders needing an exchange. b) Fail to reject the null hypothesis. At the 5% significance level there is not enough evidence to conclude the size guide will lower the population proportion of orders needing an exchange. c) There is a 1.8% chance the size guide will lower the proportion of orders needing an exchange.  Blank/Part 4:  Based on your answer to blank/part 3, which type of error are you at risk of making?