## Solution Explanation To find the **0.5% yield strength** from a stress-strain curve: 1. **Locate 0.5% strain** on the x-axis (ε, %). 0.5% strain means ε = 0.5. 2. **Draw a line parallel to the initial linear (elastic) portion** of the curve, starting at ε = 0.5%. Where this line intersects the stress-strain curve is the **0.5% yield strength**. 3. **Estimate the stress** at this intersection point. ### Analysis from the Graph - The initial linear region is up to about 1% strain. - At ε ≈ 0.5%, the corresponding stress is a little below 80 ksi (from the y-axis). - 80 ksi = 80,000 lbf/in² - Looking at the options: - 84,000 lbf/in² (590 MPa) - 98,000 lbf/in² (690 MPa) - 70,000 lbf/in² (480 MPa) - 76,000 lbf/in² (530 MPa) ### Closest Answer From the graph, at 0.5% strain, the stress is just slightly above 76,000 lbf/in², but not quite 84,000 lbf/in². The **closest answer is:** **76,000 lbf/in² (530 MPa)** --- **Final Answer:** > **76,000 lbf/in² (530 MPa)** --- **Note:** The Poisson's ratio is not needed for this question.