Drainage basin - the area of land drained by a river.
Catchment area - the area within the drainage basin.
Watershed - the edge of highland surrounding a drainage basin which marks the boundary between two drainage basins.
Source - the beginning or start of a river.
Confluence - the point at which two rivers or streams join.
Tributary - a stream or smaller river which joins a larger stream or river.
Mouth - the point where the river comes to the end, usually when entering a sea.
Hope this helped :)
Answer:
Core is made up of <em>a</em><em>l</em><em>l</em><em>o</em><em>y</em> which is the combination of <em>I</em><em>r</em><em>o</em><em>n</em><em> </em><em>,</em><em> </em><em>N</em><em>i</em><em>c</em><em>k</em><em>e</em><em>l</em><em> </em><em>,</em><em> </em><em>G</em><em>o</em><em>l</em><em>d</em><em> </em><em>,</em><em> </em><em>P</em><em>l</em><em>a</em><em>t</em><em>i</em><em>n</em><em>u</em><em>m</em><em> </em>and <em> </em><em>U</em><em>r</em><em>a</em><em>n</em><em>i</em><em>u</em><em>m</em><em>.</em>
(From Google)
The Southern Indian Ocean I think
