Answer: a)Copper and tin
Explanation: Copper and tin came into use at very early ages in the form of utensils, ornament etc. They were discovered in a way that it is possible for the people of early ages to extract these metals and melt them to give it some kind of shapes and utilize it for their daily living.People also started using these metals in the form of alloys as well which expanded the used of metals like copper, tin , bronze etc. Thus, correct option is copper and tin.
Answer:
Probably because it either has inappropiate language or has been traced back to a test.
Answer:
Helium
Explanation:
The sun produces energy by fusing hydrogen atoms into helium atoms. This is a nuclear fusion that occurs at the suns core.
