Correct Answer: B. homogenous population

Correct Answer: D. Population density

Explanation

6(a) Effects of maize weevil on maize grains are: (i) destroys the endosperm, thereby, reducing the food value grains. ( (ii) reduces viability of infested grains as the embryos are damaged. (iii) reduces market value of infested grains. (iv) predisposes infested grains to other pathogenic microorganisms attack. (v) reduces the quantity of the maize grains and produce.

(b) General control measures of insect pests of grains in storage are: (i) Early harvesting of grains such as maize, guinea corn and cowpea reduces the level of infestation and damage in the field. (ii) Proper cleaning and fumigation of sores before grains are stored helps to reduce the level of infestation and damage. (iii) Storage of maize -cobs with or without the husks and guinea corn heads over fire places where they are regularly smoked has been found to be effective in controlling the insect pests (iv) Storage and fumigation of she in silos or sealed polythene bags/ containers. (v) maize cob stored in cribs and unthreshed guinea corn heads in rhumbus should be treated with insecticides such as Actellic 25 dust or liquid, (vi) Grains should be dried to reduce their moisture content to the desired level to kill the eggs and larva of pests.

(c) Insect vectors of crop diseases are: (i) groundnut rosette - aphid (ii) maize streak - Piercing and sucking insects e.g capsid or scale insects. (iii) cassava mosaic - white fly.

Correct Answer: (c) consult

Correct Answer: C. credit ceiling

Explanation

Credit ceiling is one of the tools or instrument of monetary policy used by central bank to control credit in an economy.

Correct Answer: A. sum of the prices

Correct Answer: D. shoulder to shoulder

Correct Answer: D. on-shore movement of cold air

Correct Answer: C. Potassium trioxocarbonate (IV)

Correct Answer: B) opportunity cost

Explanation

This Economics question is asking about a concept that explains what happens when a government decides to use resources to build a school instead of a highway. The question wants to know which of the provided options best describes this concept.

The correct answer is option B, which is opportunity cost. Opportunity cost is the value of the next best alternative that is forgone when a choice is made. This means that when the government chooses to use resources to build a school, the opportunity cost is the highway that could have been built with those same resources.

Opportunity cost is an important concept in Economics because it helps individuals and governments make better decisions by considering the costs and benefits of different choices. By understanding opportunity cost, they can make choices that maximize their resources and achieve their goals.

To learn more about opportunity cost and other important Economics concepts, please see the relevant sections of your recommended Economics textbooks.