http://www.vaderstad.com/en/knowhow/soil-basic The building blocks of soil The soil that is cultivated to create a seedbed only consists to half of solid material, while the remainder consists of pores filled with…
http://www.eschooltoday.com/rocks/what-is-a-rock.html They are very tiny grains of different minerals, compressed together in chemical reaction to form a bigger mass. Rocks make up non-water part of the earth’s crust. A mineral and a…
http://en.wikipedia.org/wiki/Radiation From Wikipedia, the free encyclopedia In physics, radiation is the emission or transmission of energy in the form of waves or particles through space or through a material medium.[1][2] This includes electro-magnetic radiation such as radio waves, visible light, and x-rays, particle radiation such as α, β, and neutron…