Interferences about the population variance

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5. [15 POINTS =5+5+5] EDUCATION EXPERTS CONDUCTED A STUDY AIMED AT DRAWING INFERENCES ABOUT PARAMETERS OF THE NORMAL POPULATION OF MIDTERM SCORES. A SAMPLE OF 25 STUDENTS WAS COLLECTED AND ITS SUMMARIES ARE SHOWN BELOW. SAMPLE MEAN = (X-BAR) = 75.4 SAMPLE STANDARD DEVIATION = (S) = 10.5ESTIMATE THE UNKNOWN POPULATION VARIANCE WITH 95 % CONFIDENCE DESCRIBE THE CONFIDENCE INTERVAL USING THE TABLE BELOW CRITICAL VALUE UPPER LIMIT LOWER LIMIT