Forces in hot extrusion is a function of the strain hardening component of the billet material.

Which one of the following manufacturing process requires the provision of 'gutters'

A moving mandrel is used in

An annealed copper wire of $$25 mm$$ diameter is drawn into a wire of $$5$$ $$mm$$ dia. The average yield stress in this operation if the flow curve of the material is given
$$\sigma = 315{ \in ^{0.54}}\,MPa$$