QUESTION $3$: STEEL

$[10$ MARKS$]$

The steel bar with a $500$ mm diameter was subjected to various loads; the test results are shown in the table below $.$

$\backslash$table$[[$Load $($N$),$Stress,Strain $($mm$)],[2850,?,0\mathrm{.}0005],[20000,?,0\mathrm{.}0040],[35750,?,0\mathrm{.}0600]]$

$3\mathrm{.}1.$ Complete the table

$(8)$

$3\mathrm{.}2$ Explain the relationship between stress and strain based on the interpretation of $3\mathrm{.}2$ Results. $(2)$

QUESTION $4$: TIMBER

$[6$ MARKS$]$

Timber is classified using various methods before it is sold to consumers. Explain how each of these methods categorise each timber.

$4\mathrm{.}1.$ Grading of structural timber

$4\mathrm{.}2.$ Durability

$4\mathrm{.}3.$ Seasonal characteristics