A spectrometer is used to make five measurements of the carbon content (in ppm) of a certa silicon wafer on each of two successive days. the result was as follow:
Day 1: 2.1321 2.1385 2.0985 2.0941 2.0680
Day 2: 2.0853 2.1476 2.0733 2.1194 2.0717
a. Can you conclude that the calibration of the spectrometer has changed from day1 to day2? use a=0.05
b. Check the assumptions for the test in (a).
C. Find a 95% confidence interval for the difference (between day1 and day2) in mean spectrometer measurements.