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Toolmakers created better farming tools as the need for them arose. These included hoes for digging soil, sickles for cutting grain, and millstones for grinding flour. In some regions, people began to work with metals, including copper. Workers heated rocks and discovered melted copper inside them. They then experimented with making the copper into tools and weapons. These proved to be easier to make and use than those made of stone.
How did people evolve technologically