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(a) State four factors which may cause a waterfall to form
(b) (i) Describe how river braids are formed
(ii) Name three features resulting from river rejuvenation

Answer Text:
a) Where a river descends over a sharp edge of a plateau encountering a sharp drop. b) Where a river descends a cliff into the sea.
c) Where a river descends a fault scarp. d) Where a river descends a sharp edge of a plateau. e) Where a river is blocked by lava flow causing water to accumulate on the upstream side and a water fall forms at the point of overflow. f) Where a resistant rock lies across a river with a less resistant one on the downstream side and the less resistant one is eroded faster
causing a rapid to be first formed, then a waterfall.
b i) -At the mature /old stage of a river, the river channel is wider and shallow
-The river flows sluggishly at low velocity due to due gradient.
-Heavy load is deposited on the river bed
-The alluvial deposit grow into island/shoals-the river is blocked and sub-divided into
smaller channels called distributaries
-The water joins again later.
-The several channels intertwining each other forms river braids
-The small islands in between them are called aits /eyots /isles
ii) -Knick Points
-River Terraces
-Incised Meanders
-Antecedent Gorges
-Water falls