a) Sketch an example of tensile loading, clearly identifying the variables that will define the tensile stress and strain. b) Give the equations defining tensile stress and strain, and hence define the Young's modulus. c) The following equations show the relationship between several moduli. State the names given to each variable. G=\frac{Y}{2(1+\nu)} \text { ii. } \quad K=\frac{Y}{3(1-2 \nu)} d) State the upper and lower limits on the Poisson ratio. e) Sketch a plot of stress against strain for a ductile solid, labelling the appropriate features and indicating where the previous moduli are applicable. f) Two different weights are placed upon two identical metal supports, causing the supports to deform. When the weights are removed the support under the lesser weight returns to its original shape, whereas the support under the greater weight remains in the new deformed shape. Explain the difference in behaviour from a microscopic (atomic) perspective.