Acid rain is a result of air pollution. Lots of different chemicals are produced whenever any type of fuel is burnt. Cars, factories and power stations all burn fuels. And they all produce polluting gases. Some of these gases react with the small droplets
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At the very edge of the visible universe, scientists can see very bright and powerful objects called “quasars.” Quasars are about the size of the Solar System. They produce more light and energy than 1,000 galaxies!
Thunder is the sudden loud noise which comes from the sky during a thunder storm. A thunder storm is a storm that makes lightning and thunder. Thunder storms can also produce flash floods, hail, strong winds, and even tornadoes.
The brain is a complex organ. It consists of gray matter (40%) and white matter (60%). The brain has three main parts: the cerebrum대뇌, the cerebellum소뇌, and the brain stem. The average weight of an adult human brain is about 1.3-1.4 kilograms. At bi
Red blood cells are sometimes simply called “red cells.” They are doing a very important job in your body. They travel through your body continuously, delivering oxygen and removing waste. A single drop of blood contains millions of red blood cells! Red
The sea appears to be blue most of the time. But the sea can be many other colors depending on particles in the water, the depth of the water, and the amount of skylight. The colors we see depend on the reflection of the visible wavelengths of light to ou
Today, glass is used to make many things. Windows, milk bottles, mirrors, doors for buildings, light bulbs, computer screens and many other things are made of glass. Glass is made by melting several minerals together at very high temperatures. Actually,
A nebula is a huge, diffuse cloud of gas and dust in space. The gas in nebulae is mostly hydrogen gas -- H2. Scientists believe that new stars form inside of nebulae. There are many kinds of nebulae such as Emission Nebulae, Reflection Nebulae, Planetar
here is not just one answer to this question. This is because not all fish have been tested for color vision. But according to scientists, the goldfish and many other fish can see in color. Color vision is the ability to see objects based not on how bri
Galaxies are huge collections of stars, dust and gas. They usually have several million to over a trillion stars. The distance across them is very great. And it can be several hundred thousand light years!
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