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Sleep is an essential function that allows our body and mind to recharge leaving us refreshed and alert when we wake up.
Paper was first made in china by Tsai Lun a Chinese court official.
How food moves through each part of the body to help break down food for energy.
Birds migrate to move from areas of low resources to areas of increasing resources.
An earthquake is an intense shaking of Earth's surface. The shaking is caused by movements in Earth's outermost layer.
A beautiful arc of colors that appears in the sky and is caused by the sun shining through rain or mist..