Match the following:

Reaming is a process used for

An $$HSS$$ drill of $$20mm$$ diameter with $$5mm$$ cone height is used to drill a through hole in a steel work-piece of $$50mm$$ thickness. Cutting speed of $$10m/min$$ and feed rate of $$0.3mm/rev$$ are used. The drilling time, in seconds, neglecting the approach and over travel, is ______________

In an open loop, point-to-point controlled $$CN$$ drilling machine, a stepper motor, producing $$200$$ angular steps per revolution drives the table of a drilling machine by one angular step per each pulse generated by a pulse generator (shown in figure). Each angular step moves the table by one Basic Length Unit $$(BLU)$$ along $$X$$ axis with a lead screw having a pitch of $$4mm.$$ If the frequency of pulse generator is doubled, the $$BLU$$ will