Hi, these are questions from my exam from the mechanical behavior of materials. I seriously screwed the exam up. Can you guys help me out? a) Provide two reasons why C is more effective than Ni in strenghtening Fe. b) Explain why single crystalline alloys with fine grains are more desirable for low temperature applications. c) Show schematically how the yield strength of an aluminum alloy may vary with aging time and explain how dislocations interact with the precipitates in different parts of the aging curve. Thanks, Ryan.