In 2016, the variance of scores in the class of OMG 321 was 21. Recently, a sample of 20 students had a variance of 25. We are interested in testing to see if there has been a significant change in the variance of scores in OMG 321. ( α = 0.05?) a) formulate the hypotheses At a 95% confidence, calculate the test statistics (chi-square value) and test the hypotheses (round the first decimal).  b) What are the critical values? What is the conclusion?  Develop the 95% interval estimate of the variance for the population. Please round to the second decimal place.  Clearly state answers please.

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