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QUESTION 24 (4 Marks) Martin purchased three units of good A. The marginal benefit of the fourth unit of A exceeds the marginal cost of the fourth unit of good A. Which of the following reasons explains why Martin should purchase the fourth unit? I. The marginal net benefit of the fourth unit is positive. Il. Buying the fourth unit will increase total benefits by more than total costs. Ill. Buying the fourth unit will increase total benefits and decrease total costs. A. I only B. I and II only C. II only D. I, II, III QUESTION 25 (4 Marks) Which one of the following statements is incorrect? A. The income elasticity of demand indicates by how much the incomes of suppliers will change if the price of the product changes by one per cent. B. The income elasticity of the demand for candles in poor households in South Africa has been estimated at -0,20. This indicates that candles are inferior goods for such households. C. The income elasticity of the demand for tea in South Africa has been estimated at 0,21. Tea may therefore be classified as both a normal good and an essential good. D. The income elasticity of the demand for biltong in South Africa has been estimated at 1,36. Biltong may therefore be classified as both a normal good and a luxury good