The zebrafish is a freshwater fish belonging to the minnow family. It is native to South Asia, it is a popular aquarium fish, frequently sold under the trade name zebra danio. It belongs to India and Sri Lanka.
Karst topography is a result of the dissolution of soluble rocks like limestone, dolomite and gypsum. Caves are formed due to weathering of rock deep underground. Cave or cavern is a natural void and is a space large enough so that a human can enter. The study of the formation and development of caves is called as Speleogenesis. Most of the formation of caves takes place in limestone rocks by dissolution.
Extensive development of dairy farming in the dairy belt of North America has been possible due to the presence of a combination of physical and economic factors. The region receives a rainfall varying between 55 and 125 cm. The rainfall efficiency is further increased by relatively lower temperature ranging between 18° and 24°C. The cattle yield more milk in a cool climate and the milk can also be kept for a longer time at lower temperature.