Arouter is used to cut locating notches on a printed circuit board. the vibration level at the surface of the board as it is cut is considered to be a major source of dimensional variation in the notches. two factors are thought to influence vibration: bit size (a) and cutting speed (b) are thought to influence the vibration level. two bit sizes (1/16 and 1/8 inch) and three speeds (40, 60, and 90 rpm) are selected, and four boards are cut at each set of conditions. the vibration level is measured on each board cut.

(a) what is the response variable?

(b) what is (are) the factor(s)

(c) what are the levels of each factor?

(d) how many replicates are there?