The data set ph .txt contains measurements from three batches of material that were made at a chemical plant. For each batch numerous pH readings were taken during the course of production. For this particular material the pH should have been consistent throughout production.
(a) Construct a histogram for these data.
(b) Discuss the sources of measurement error in this study. What could have been done to minimize the measurement errors?
(c) Construct a histogram for each individual batch.
(d) Write a short report based on the histograms for these data.