Explanation:
(a) Three differences between light industries and heavy industries

Light industries	Heavy industries
(i) They produce relatively small light weight goods, e.g shoes(ii)-The products of light industries are mainly final or consumer goods(iii) It usually employs a lot of female workers	(i) They produce heavy and bulky goods, e,g iron and steel(ii) Products are not final nor consumer good rather they are used in construction or manufacturing industries(iii) It employs male workers due to the nature of work involved

(b) Four reasons why light industries are more prevalent than heavy industries in tropical Africa are:
(i) Lack of capital; Poor funding leads to the establishment of light industries than heavy industries
(ii) Lack of technical know-how: Africans do not have the skills for heavy industrial operations
(iii) Lack of raw materials; Raw materials: for heavy, industries are lacking in African countries
(iv) Africans generally tend to engage in production of consumable goo than non-consumable goods because of the low level of development.