A researcher wants to conduct a before/after study on 12 subjects to determine if a treatment...

A researcher wants to conduct a before/after study on 12 subjects to determine if a treatment results in any difference in scores. Scores are obtained on the subjects both before and after the treatment. After subtracting the after scores from the before scores, the average difference is computed to be 3.40 with a sample standard deviation of 1.21. Assume that the differences are normally distributed in the population. If the researcher wanted to construct a 98% confidence interval for the difference between the (after - before) means, the t value to be used in the computations will be

A) 2.3027

B) 2.3281

C) 2.6810

D) 2.7181

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Expert Solution

milcah answered 10 months ago

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