A steel bar $$200$$ $$mm$$ in diameter is turned at a feed of $$0.25$$ $$mm/rev$$ with a depth of cut of $$4$$ $$mm.$$ The rotational speed of the work piece is $$160$$ $$rpm.$$ The material removal rate in $$m{m^3}/s$$ is

Internal gear cutting operation can be performed by

Quality screw threads are produced by

A good cutting fluid should have