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)
All it means is the totality of what is to be taught in a school system.
herbivores
Explanation:
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