The adjacent graph shows the extension \( (\Delta l) \) of a wire o...

The adjacent graph shows the extension \( (\Delta l) \) of a wire of length \( 1 \mathrm{~m} \) suspended from the top of a roof at one end and with a load \( w \) connected to the other end. If the cross-sectional area of the wire is \( 10^{-6} \mathrm{~m}^{2} \), calculate from the graph the Young's modulus of the material of the wire.
(2003, 2M)
(a) \( 2 \times 10^{11} \mathrm{~N}^{2} \)
(b) \( 2 \times 10^{-11} \mathrm{~N} / \mathrm{m}^{2} \)
(c) \( 3 \times 10^{12} \mathrm{~N} / \mathrm{m}^{2} \)
(d) \( 2 \times 10^{13} \mathrm{~N} / \mathrm{m}^{2} \)