(a) Effects of rural-urban migration on agricultural production: (i) scarcity of labourers leading to high labour cost (ii) high cost of labour will lead to high cost of production (iii) decreased food and cash crop production (iv) decreased animal production (v) decrease in export and hence GDP (Gross Domestic Product) (vi) poor adoption of agricultural innovations.
(b)(i) Effect of demand on production given a constant supply situation: (1) increase in demand results in increase in agricultural production and (2) decrease in demand results in decrease in agricultural production. (ii) Effect of supply on production given a constant demand: (1) demand is directly proportional to income such that more demand means more income and (2) less demand leads to less income.
(c)(i) Effect of demand on farmers' income when price is constant: (1 )demand is directly proportional to income such that more demand means more income and (2) less demand leads to less income (ii) Effects of supply on farmer's income when demand is constant: (1) increased supply decreases income as prices fall and. the perishable produce will waste away and (2) decrease in supply leads to higher income as price rises.
(d) Roles of a manager in a farm enterprise: (1) plans when and what to produce/decision making (2) supervises the duties of staff (3) co-ordination of farm activities (4) ensures effective combination of resources (5) determines the quantity of and what to sell and buy/ farm gate price (6) determines for how much a produce should be sold (7) ensures adequate record keeping (8) supervises the accounting system (9) budgets for the farm (10) organizes various tasks of the farm enterprise.