A steel wire (1.5 mm²) and a copper wire (2.0 mm²), both 1.6 m long, hang side by side and hold up…

Step 1. Share. $Y_sA_s : Y_cA_c = 3.0 : 2.2$, so steel takes $\dfrac{3.0}{5.2} \times 520\ \text{N} = 300\ \text{N}$ and copper $220\ \text{N}$.

Step 2. Stresses. $\dfrac{300\ \text{N}}{1.5 \times 10^{-6}\ \text{m}^2} = 2.0 \times 10^{8}\ \text{Pa}$ and $\dfrac{220\ \text{N}}{2.0 \times 10^{-6}\ \text{m}^2} = 1.1 \times 10^{8}\ \text{Pa}$.

Step 3. Stretch. $\dfrac{300\ \text{N}}{1.5 \times 10^{-6}\ \text{m}^2} \times \dfrac{1.6\ \text{m}}{2.0 \times 10^{11}\ \text{Pa}} = 1.6 \times 10^{-3}\ \text{m}$.