Which is correct and most complete (according to this book)?

a. With experts in-the-loop, it is rarely (if ever) critical to consult SOP settings.

b. They likely made some Type I errors by assuming that all factors mattered.

c. They could have used 12 batches based on a Plackett Burman (PB)

array and likely avoided errors

d. Up to 3 additional factors could have been used with only 16 batches structured according to a regular fractional factorial (FF).

e. All of the above are correct.

f. All of the above are correct except

(a) and (e).