(a) Ways in which air transportation is different from water transportation
(i) Air transportation is faster than water transportation
(ii) Water transport is more suitable for carrying bulky goods than air transport
(iii) Air transport can be used to reach the most remote, most distant and most inhospitable places on earth (in terms of climate) water transport is limited to water bodies only
(iv) water transport is interrupted by hazards of rapids, falls and fogs while air transport is disrupted by visibility alone
(v) Air transport costs more than water transportation in the hauling of goods and services
(vi) Air transport is used for movement of human beings, perishable and precious goods ti water transport.
(b) Major contributions of transportation to national development:
(i) Enhances communication
(ii) Promotes trade
(iii) Generates employment
(iv) Generates revenue
(v) Income for workers
(vi) Promotes tour
(vii) Enhances military movement
(c) problems of water transportation in tropical Africa:
(i) Capital intensive dredging of harbours and waterways
(ii) Seasonal fluctuation of water level
(iii) Presence of water-weeds
(iv) Presence of rapids and falls
(v) Pilfering of goods at seaports
(vi) Sand spits and sand bars
(vii) Inadequate goy to carry at some seaports.