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Question: A researcher collected data from a random sample of 25high school freshmen and found the mean of...

A researcher collected data from a random sample of 25 highschool freshmen and found the mean of the sample to be 85.40 on theTest of Critical Thinking (TCT). She also calculated the standarddeviation from the sample and discovered the value was 12.30. Theaverage score on the Test of Critical Thinking for all high schoolseniors in a large school district is 90.00. The researcher wantsto know if the mean TCT of the 25 high school freshmen in therandom sample is different from the population’s (i.e., high schoolseniors) TCT mean.

e.What decision should be made about the null hypothesis? In otherwords, should you reject or retain the null hypothesis?
f. Construct a 95% confidence interval around the sample mean of85.40. Does this confidence interval contain the population mean of90.00?
g. Provide a brief conclusion regarding your findings. Use yourpowerpoint lecture slides for writing out the interpretation ofyour results.
[ME: What decision should be made about the null hypothesis? Inother words, should you reject or retain the null hypothesis? (10p)e. f. Construct a 95% confidence interval around the sample mean ofgaps. Does this confidence interval contain the population mean of90.00? (Extra credit:10p) Provide a brief conclusion regarding yourfindings. Use your powerpoint lecture slides for writing out theinterpretation of your results. (10p) g.]