What Is Nitrogen Dioxide? You can’t see nitrogen dioxide. It’s a gas made by cars, trucks, buses, power plants, and factories. Too much nitrogen dioxide causes smog and acid rain. It can make people sick, too. Nitrogen dioxide is partly to blame for … Read more
A laser is a thin, powerful beam of light. Lasers use mirrors to focus light energy. People use lasers every day. You may even have a laser at home. A DVD player uses a laser to read the information on … Read more
stop the spread of COVID-19. It’s not just schools that are meeting remotely. Even the justices of the Supreme Court of the United States are hearing their cases remotely—over the phone. This is the first … Read more
Have you heard about “social distancing”? Social distancing is a way to stop the spread of COVID-19, the new coronavirus. Scientists believe that the virus spreads through the air when an infected person coughs, sneezes, … Read more
The Constitution of the United States says that a census should take place every ten years. This year is one of those years. What happens in the Census? A census counts the people living in … Read more
Riding a bicycle is lots of fun. Riding is great exercise and a fun way to get to places you want to go. But every year, about 300,000 kids go to the hospital for bike … Read more
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