Answer: C. 
Step-by-step explanation:
The confidence interval for difference of two population mean is given by :-

Given : Level of significance : 
Then , significance level : 
Critical value : 


Hence, a 99% confidence interval for the difference between the mean wait times of everyone who rode both rides 
Answer:
9
Step-by-step explanation:
12 divided by 4=3 3X3=9
Answer:
4. (d, the last one)
5. (a, the first one)
Step-by-step explanation:
That's a simple question.
Ans: If both numbers can be divided to equal a whole number, then it can be simplified.
Example: 35:7 (this is your ratio) divided by 7 = 5:1
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