Answer: the top one
Explanation: hope this helps
The wise and careful use of energy is called CONSERVATION
Answer:
Springs are made of a variety of materials including copper and various forms of steel. The most common is high carbon steel as it is cheap, easy to work and a couple of other important properties.
Copper springs exist as well, but copper is more expensive than steel. However, in an environment where corrosion resistance is important, copper springs are a good alternative.
Explanation:
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