(a) List four cereal crops grown in West Africa [2marks] (b) State three benefits of forest to the economic development of your country.[3marks] (c) With th...

(a) Four cereal crops grown in West Africa

1. Maize
2. Rice
3. Sorghum (guinea corn)
4. Millet

(b) Three benefits of forests to the economic development of a country

1. Forests supply timber, fuel wood and other raw materials for industries such as sawmilling, paper, gum and latex industries.
2. They provide employment and income for rural people and also generate revenue and foreign exchange for government.
3. Forests protect the environment by checking erosion and desertification, protecting water catchment areas and serving as windbreaks.

(c) Life cycle of the variegated grasshopper (Zonocerus variegatus)

The variegated grasshopper undergoes incomplete metamorphosis. The female lays egg pods in the soil, usually at the beginning of the rainy season. The eggs hatch into wingless nymphs. The nymphs resemble small adults and feed actively, moulting through several instars as wing buds develop. After the final moult, a fully winged adult emerges. The adult mates and lays eggs in the soil, thereby repeating the cycle. There is no pupal stage.

(d) Three cultural methods of controlling crop pests

1. Crop rotation.
2. Timely planting and harvesting.
3. Regular weeding and destruction or burning of crop residues that harbour pests.

(e) Two uses of oil palm

1. The palm oil obtained from the fruit mesocarp is used for cooking and for making soap.
2. Palm kernel oil is used in making soap, margarine and other industrial products.