Explanation:



(a)Meaning of subsistence agriculture: A farming system whereby the farmer uses traditional tools with poor inputs on a small piece of land to produce food for his family consumption.
(b) Discussion on the interdependence of agriculture and industry:
(i) Tools, implements and machinery industries:
-The increasing high demand for agricultural produce and the need to process and store them have given rise to mechanization.
- Farm machinery and implements have been manufactured by various industries and local artisans to carry out various operations in agriculture.
- Local blacksmithing workshops produce tools such as hoes and machines for grinding and milling of farm produce.
(ii) Processing Industries:
- Most agricultural produce are perishable and bulky in nature.
-They require some form of processing and storage prior to their consumption and marketing in future.
-This has led to the establishment of processing industries e.g. industries processing fruits, tubers, milk, etc.
(iii) Agro-chemical industries:
-In order to boost agricultural production, farmers' demand for agro-chemicals such as fertilizers, pesticides, herbicides and fungicides has been on the increase.
-Veterinary drugs as well as feed additives are also required in animal production.
(c)(i) Meaning of farm surveying: Farm surveying is the process of measuring and mapping out the position, size and boundaries of a farm land.
(ii) on the use of the 3, 4, 5 method in farm survey.

-From the point in figure X where the right angle is to be marked, 3 metres are measured back to point C.
- Pegs are stuck into the ground at A and C.
-Apiece of cord 4 metres long is tied to the peg at A and one 5 metres long tied to the peg at C.
- The two pegs are stretched out and another peg is stuck into the ground where the cords meet at B. The angle marked at A is now a right angle.