(a) A farmer purchased a tractor in the year 2000 for D 12, 000.00. In 2009, the tractor was
sold for D 3,000.00 as it was no longer economical to keep. Calculate the:

(i)  useful life of the tractor;
(ii) salvage value of the tractor;
(iii) total depreciation of the tractor;
(iv) annual depreciation of the tractor.  

 

(b) Describe the following terms as used in agricultural economics:
(i)  demand schedule;
(ii) supply curve.  

 

(c) List four agricultural extension agencies in West Africa. 

 

(d) State four ways through which soils are enriched with nitrogen.