(a) Give four reasons why countries engage in world trade (b) How have these reasons affected the volume of trade between Nigeria and her neighbouring count...

(a) Give four reasons why countries engage in world trade 

(b) How have these reasons affected the volume of trade between Nigeria and her neighbouring countries?

(C)(i) Name any two sea routes through which Nigeria trades with the outside world
(ii) Indicate one commodity that Nigeria engages exports through each route