What kind of machine tool is likely to be most economical for producing rotationally symmetric parts of the following characteristics:

(a) requires turning, drilling, boring, and parting off, at production rates os 10,000 parts per month;

(b) as (a) but only 10 parts per month;

(c) a very slender high precision part requiring turning and parting off, at production rates of 1000 parts per month;

(d) as (c), bu tonly 10 parts per month;

(e) as (a) but with a transverse hole;

(f) as (b), but with a transverse hole.