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b-false.
4-an estuary consists of : a- river water.
b-salt water.
c-a mixture of salt and fresh water.
5-estuaries : a- are very important to people since they can be used as
harbors,or for sailing and trading.
b-do not have any economic or commercial benefit.
6-estuaries : a-have a limited capacity to absorb pollution .
b-can not be polluted since tides help to keep them pure and clean.
7-the chemical composition of water in estuaries :
a-is affected by river discharge and tidal mixing.
b-is not affected by the surrounding water bodies ,a s they are isolated
water bodies.
8-estuaries : a- are stressful for marine organisms.
b-different kind of marine organisms thrive and flourish there.
9-estuaries are fertile and can support large population of organisms :
a-because different kind of marine organisms lay their eggs there.
b- because of the river supply of nutrients,reduction in competition for
food , space and limited predation.
10-plankton production in estuaries :
a- Are regular.
b- Are irregular.
11-Bacteria abound in estuaries : a- true.
b-false.
12-fish species found in estuaries :
a-have high physiological tolerances to environmental changes.