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| Q. |
Percentage of lead in lead pencils is – |
| A. | "0" |
| B. | 31-66 |
| C. | 40 |
| D. | 80 |
| Answer» A. "0" | |
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Explanation: There is no lead in pencils. Rather, the core is made up of non-toxic mineral called graphite. The common name "pencil lead" is due to an historic association with the stylus made of lead in ancient Roman times. Most pencil cores are made of graphite mixed with a clay binder, leaving grey or black marks that can be easily erased. Graphite pencils are used for both writing and drawing, and the result is durable: although writing can usually be removed with an eraser, it is resistant to moisture, most chemicals, ultraviolet radiation and natural aging. |
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