A digital camera maker produces three different models: (1) base model, (2) zoom model, and (3) zoom model with extra memory. Data for the three models are shown in the table below. The three models have been on the market for one year, and the first year's sales are given in the table. Also given are critical-to-quality (CTQ) characteristics and total defects that have been tabulated for the products sold. Higher model numbers have more CTQ characteristics (opportunities for defects) because they are more complex. The category of total defects refers to the total number of defects of all CTQ characteristics for each model. For each of the three models, determine
(a) The number of defects per million opportunities and corresponding sigma level,
(b) The number of defects per million and corresponding sigma level, and
(c) The number of defective units per million and corresponding sigma level.
(d) Does any one model seem to be produced at a higher quality level than the others?
(e) Determine aggregate values for DPMO, DPM, and DUPM and their corresponding sigma levels for all models made by the camera maker.

Model Annual sales CTQ characteristics 62,347 31,593 18,662 16 23 29 Number of defective cameras 127 109 84 Total number of defects 282 429 551