Answer: (11.95, 14.11)
Explanation:
Let x be a random variable that represent the number of years of education.
Given: Sample size : n= 26
Sample mean : 
Sample standard deviation : s = 3.22
Significance level : 
Degree of freedom: df = n-1 = 25
Critical t-value for
and df = 25 will be

90% confidence interval for mean:

A 90% confidence interval for the mean number of years of education = (11.95, 14.11)
The balance of power can be maintained through <em>alliances. </em>This system allows the countries to plan and agree or disagree with decisions that concern each other. This way, a country that likes to emerge as a super power will be prevented itself from doing so.
Answer:
Explanation:
The would want to gain independence if a certain type feels they have no voice, or are having to many/to strict of rules. The problems would be, creating new rules, new currency, new protection etc.
The answer to this question is <span>when two variables are correlated, we cannot be sure what is causing the correlation.
For example, let's there is a study that found an increase in consumption in tofu lead to an increase in breast cancer.
Even if it's true that those two really correlated (let's just assume it), we wouldn't be able to know why it is correlated without further researches.</span>