(b) Four ways in which relief of Africa poses problems to the construction of trans-African highway from Cape of Good Hope to Cairo are:
(i) Presence of many highlands such as Kilimanjaro, Kenya highlands, etc.
(ii) Presence of many rivers which will demand high cost of constructing bridges across the rivers
(iii) Presence of deep valleys e.g Great East rift valley
(iv) Effects of wind erosion and deposition can disrupt the construction of such road.
(c) These problems can be minimized by;
(i) Construction of roads on fairly lowland areas
(ii)Avoiding presence of high mountains and valleys
(iii)Avoiding the presence of big rivers and planting trees along the roads in desert area.