Which is correct and most complete based on how the designs are constructed?

a. Central composite designs do not, in general, contain center points.

b. A BBD design with seven factors contains the run -1, -1, -1, -1, -1, -1,

-1.

c. Central composite designs contain Resolution V fractional factorials.

d. CCDs and BBDs were generated originally using a computer.

e. All of the above are correct.

f. All of the above are correct except

(a) and (e).