$$NC$$ contouring is an example of

Consider the following characteristics:

$$1.$$ Single machine tool.
$$2.$$ Manual materials handling system
$$3.$$ Computer control.
$$4.$$ Random sequencing of part to machines.

Which of the above characteristics are associated with flexible manufacturing system?

A $$\phi \,\,25$$ $$mm$$ hole is pierced in a $$t=2.5mm$$ thick steel sheet having shear strength $$\tau = 350\,\,MPa.$$ If the diametral clearance is given by the expression $$C=0.0064$$ $$t$$ $$\sqrt \tau ,$$ the die diameter (in $$mm$$), punch diameter (in $$mm$$) and punch force in $$(kN)$$ respectively are

Consider the following statements:
In comparison to hot working, in cold working,
$$1.$$ Higher forces are required
$$2.$$ No heating is required
$$3.$$ Less ductility is required
$$4.$$ Better surface finish is obtained.

Which of the statements given above are correct?