The relationship between true strain $$\left( {{\varepsilon _T}} \right)$$ and engineering strain $$\left( {{\varepsilon _E}} \right)$$ in a uniaxial tension test is given as

With respect to metal working, match Group A with Group B:

In a rolling process, the state of stress of the material undergoing deformation is

A solid cylinder of diameter $$100$$ $$mm$$ and height $$50$$ $$mm$$ is forged between two frictionless flat dies to a height of $$25$$ $$mm.$$ The percentage change in diameter is