Question A: 5 points

A production process whose standard deviation is known to be 1.2 cm has been recalibrated to produce, on average, units that are 100 cm long. After the latest round of adjustments, those responsible for this process are still unclear as to the mean size of outputs from this process. Suppose a random sample of 27 observations was taken after the latest adjustment and exhibited a sample mean of 95.2 cm.

1.What would a 95% confidence interval for the mean be? [Show your code in "R Code" section. Show the answer in "Answer" section. Leave "Comments" section blank.]

2.What would it suggest with regards to whether they have this process properly recalibrated? Why? [Leave "R Code" and "Answer" sections blank. Include the phrase "recalibrated" or "not recalibrated" along with a justification in a few sentences in "Comments" section.]