A non standard thread of pitch $$3.175$$ $$mm$$ is to be cut on a lathe having lead screw of pitch $$6$$ $$mm.$$ A change gear set provided with the lathe has one gear each with the following number of teeth: $$20, 30, 40, 50, 60, 70, 80,$$ $$90, 100, 110, 120, 127.$$ The correct pairs of change gears $$\left( {a/b\,\,x\,\,c/d} \right)$$ for machining the given thread are (assuming that the transmission ratio of the rest of the kinematic train between the lathe spindle and lead screw is equal to

For machining the circular arc shown in the figure below on a $$NC$$ machine, the interpolation parameters $$(I.K)$$ and the incremental movements in the direction of the $$X$$ and $$Z$$ axes are programmed as

Given that the notations of robot joints are $$L$$-linear, $$O$$-orthogonal, $$R$$-rotational, $$T$$-twisting, and $$V$$-revolving, the anatomy of a polar configuration robot is described by the alphabetical string