Answer:
· Irrigation schemes are a necessity in many countries as they supply the countries with sufficient water to produce food to meet their increasing food demand (Fanadzo, 2012).In South Africa, the Vaalharts Irrigation Scheme (VHIS) is a large irrigation scheme utilising water from the Vaal River via numerous gravity fed canals ().The return flow from the VHIS enters the Harts River (via numerous ...
Explanation:
First turn 18% to a decimal, which is .18, then multiply it by 450.
450 x .18 = 81
A reef than surrounds a volcanic island is an : Atoll
Atoll usually takes shapes in a form of ring that surround the areas of volcanic island that consist of corals. It usually only exist in warm waters, so volcanic islands will provide perfect environment for the corals
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