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Based on data from the Vision Council, 21% of adults in the US require vision correction. If 8 adults are randomly selected from the US. The probability that exactly 2 of them require vision correction is (Fill in the numerical value. Round to one decimal place).           

A simple random sample of 49 women has a mean height of 63.5 inches and assumes the population standard deviation is 3.5 inches. The 99% confidence interval for the population mean is:

The table below shows the results for 120 rolls of a die. These results will be used to test if the die is fair. The null hypothesis would state that the population proportion for each result is:   Result 1 2 3 4 5 6 Frequency 24 14 28 18 20 16   (Fill in the numerical value. Report the value with 2 decimal places.) 

A one-sample t‐test is conducted with H A: population mean < 10. If t = –2.46 and df = 25, the p‐value is:

The table below shows the gender and selected drink of 100 persons randomly sampled to choose between two coffee drinks, A and B. The researcher wants to test: H0: Gender and drink choice are independent HA: Gender and drink choice are not independent   Drink A Drink B Men 25 20 Women 30 25 The observed chi square test statistic is:   (Fill in the numerical value. Report the value with 2 decimal places.)   

We have a box model which has a 50% chance of giving a ticket worth 75, a 20% chance of giving a ticket worth 95, and a 30% chance of giving a ticket worth 125. Which histogram above is most likely to be an empirical histogram for drawing 50 times from the box and taking the sample mean?

Regarding the test statistic in the Analysis of Variance (Select the correct choice)     

Is a good practice in research that investigators decide which hypothesis to test only after they have seen the data.  (Select true of false)  

What percentage of the subjects in the above density histogram has a height between 74 and 76 inches? (no values fall directly on a bin cutpoint)  

Jannick is a huge sports fan. When he goes to online forums, he clicks “like” on posts from people who support his favorite team and “dislike” on posts from people who support other teams. Jannick’s tendency to favor posts from people in his group is best an example of ______.