Duralumin is used for the manufacture of aircraft because duralumin is

Options

A. a bad conductor of heat and electricity
B. more durable and has resistance to corrosion
C. very light and possesses high tensile strength
D. All of the above

Explanation

**Step-by-Step Solution:**

1. **Understanding Duralumin**: Duralumin is an alloy primarily made of aluminum, with copper and other elements added to enhance its properties.

2. **Conductivity**: One of the key properties of duralumin is that it is a poor conductor of heat and electricity. This is important for aircraft because it helps prevent the accumulation of electric charges and minimizes heat transfer, which can be crucial in emergencies.

3. **Durability and Corrosion Resistance**: Duralumin is known for its durability and resistance to corrosion. Aircraft are exposed to various environmental conditions, and using a material that can withstand corrosion ensures the longevity and safety of the aircraft structure.

4. **Lightweight and High Strength**: Another significant characteristic of duralumin is that it is lightweight while possessing high tensile strength. This is essential for aircraft as it helps maintain aerodynamics and allows the aircraft to be strong enough to withstand the stresses of flight.

5. **Conclusion**: Given all these properties, duralumin is an ideal material for aircraft manufacturing. Therefore, the answer to the question is that duralumin is used for the manufacture of aircraft because it is a poor conductor of heat and electricity, is durable and resistant to corrosion, and is lightweight with high strength. Thus, the correct answer is option D: All of the above are correct.

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