Space

This article is about the general framework of distance and direction. For the space beyond Earth's atmosphere, see Outer space. For the keyboard key, see Space bar. For other uses, see Space (disambiguation)

Space is the boundless three-dimensional extent in which objects and events have relative position and direction.^[1] Physical space is often conceived in three linear dimensions, although modern physicists usually consider it, withtime, to be part of a boundless four-dimensional continuum known as spacetime. อ่านต่อ

Paper

   Paper is a thin material produced by pressing together moist fibres of cellulosepulp derived from wood, rags or grasses, and drying them into flexible sheets.It is a versatile material with...

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Deserts

Deserts cover about one fifth of the Earth’s surface and occur where rainfall is less than 50 cm/year. Although most deserts, such as the Sahara of North Africa and the deserts of the southwestern U.S. ..อ่านเพิ่มเติม

Cave

 A cave or cavern is a hollow place in the ground,^[1][2] especially a natural underground space large enough for a human to enter. Caves form naturally by the weathering of rock and often extend deep underground. The word cave can also refer to much smaller openings such as sea caves, rock shelters, and grottos. ...อ่านเพิ่มเติม