1. **Problem Statement:** We need to verify the calculation of the maximum stress, which the professor states should be 39.5. 2. **Formula for Maximum Stress:** The maximum stress in a material under bending is given by the formula: $$\sigma_{max} = \frac{M c}{I}$$ where: - $M$ is the bending moment, - $c$ is the distance from the neutral axis to the outermost fiber, - $I$ is the moment of inertia of the cross-section. 3. **Important Rules:** - Ensure units are consistent. - Calculate $M$, $c$, and $I$ correctly. - Use correct substitution and simplification. 4. **Intermediate Work:** - Calculate or verify $M$ (bending moment). - Calculate or verify $c$ (distance to outer fiber). - Calculate or verify $I$ (moment of inertia). 5. **Substitute values:** $$\sigma_{max} = \frac{M c}{I}$$ Assuming values from the problem (not provided), substitute and simplify. 6. **Simplify fractions and cancel common factors:** $$\sigma_{max} = \frac{\cancel{M} \times \cancel{c}}{\cancel{I}}$$ (Show actual cancellation if values are given.) 7. **Final Answer:** If the calculation matches 39.5, then the professor's result is correct. If you provide the specific values for $M$, $c$, and $I$, I can verify the exact calculation step-by-step.