A random sample of second year business students at a small Canadian university were polled by a researcher attempting to establish a relationship between hours of study in the week immediately...

A random sample of second year business students at a small Canadian university were polled by a researcher attempting to establish a relationship between hours of study in the week immediately preceding a major midterm and the marks received on the exam. The data follow:

            Student           1    2    3    4    5     6    7    8    9  10

            Hours
25  12  18  26  19  20  23  15  22   8

            Exam(%)
93  57  55  90  82  95  95  80  85  61

(∑(Hours)=188 ∑Hours^2=3832  ∑(Exam%)=793     ∑(Exam%)^2=65,143 ∑(Hours)(Exam%)XY=15,540

What is the 95% confidence interval for mean exam performance of students who spend 25 hours studying?