(a) Write the full meaning of the acronyms of the following non-governmental agricultural organizations:
(i) WARDA;
(ii) IITA;
(iii) FAO;
(iv) ILCA. 

(b) Mention six ways in which agriculture is of benefit to rural communities. 

(c) List four liming materials used in agriculture. 

(d) Give four examples of sedimentary rocks.