A laser is a thin beam of light. People use lasers all the time. You may have a laser at home. A DVD player uses a laser to read a DVD. A cashier uses a laser to read bar codes.
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Two doctors made a tool. It can help people who … read more
Many Americans come from different places around the world. People … read more
September 15th to October 15th is Hispanic Heritage Month. Hispanic-Americans … read more
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