Question

3. Why can't our elbows bend backwards? Do
4. Why does a blacksmith use heat to make various tools in his business?
5. A bag of cement kept in the open gets soaked in rain. What will be its condition on
the next day?​

Answer 1

3. Structurally joints don't bend both ways because there are physical components within their design that prevent or resist motion. This could be bone, such as the elbow joint, or it could be ligamentous restraint, such as in the knee. All joints in the body are a compromise between mobility and stability.

4. Blacksmiths work by heating pieces of wrought iron or steel until the metal becomes soft enough for shaping with hand tools, such as a hammer, an anvil and a chisel. ... Because they must be able to see the glowing color of the metal, some blacksmiths work in dim, low-light conditions, but most work in well-lit conditions.

5. answer is in the pic

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