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Question 12 marks
Correct option: B
Correct option: B. Opportunity cost is the value of the next best alternative forgone when a choice is made. Here the next best alternative stated is earning $400. A is incomplete because the ticket price is a monetary cost, not necessarily the opportunity cost. C incorrectly includes every alternative rather than the next best alternative. D is unrelated to the choice.Question 22 marks
Correct option: A
Correct option: A. With at least one factor fixed, successively adding a variable factor can eventually cause its marginal product to fall. Total output can still rise, so B is wrong. Economies of scale concern changes in long-run average cost as scale changes, not the short-run change described, so C is wrong. D contradicts the stated fall in additional output.Question 32 marks
Correct option: B
Correct option: B. A binding maximum price is below equilibrium. At that lower price, quantity demanded is greater than quantity supplied, creating a shortage. A describes the opposite imbalance. C is incorrect because a price control does not itself shift the demand or supply curves. D contradicts the imposed maximum.Question 42 marks
Correct option: B
Correct option: B. GDP measures the value of final goods and services produced within a territory during a period. The machine is produced overseas, so it is not part of Hong Kong GDP. A confuses domestic production with residents' expenditure. Currency of payment does not determine where production is recorded, so C is wrong. The machine is an import, not an export, so D is wrong.Question 58 marks
5(a): Resources such as oven time and labour are limited relative to possible uses (1 mark for scarcity). The bakery therefore has to choose how to allocate resources between bread and cakes (1 mark). Choosing one use means giving up the next best alternative; this forgone alternative is the opportunity cost (1 mark). 5(b): 30 loaves are forgone to make 10 cakes (M1). Opportunity cost per cake = 30 / 10 = 3 loaves (A1). Correct unit and interpretation, 3 loaves of bread forgone per cake, (A1). 5(c): One valid reason, such as investment in a more productive oven, improved production technology, an increase in skilled labour, or better access to productive resources (1 mark). Explanation that this raises the maximum feasible output of one or both goods (1 mark).
Question 610 marks
6(a): Since the meals are a normal good, higher income raises demand (1). Demand shifts right; this is a change in demand caused by a non-price determinant (1). A change in quantity demanded is movement along a given demand curve caused by a change in the good's own price (1). 6(b): A correct diagram shows D₀ shifting right to D₁ while S₀ is unchanged (M1). The new intersection is at a higher price (A1) and a greater quantity (A1). Explanation: at the original price, the increase in demand creates excess demand; price is bid up, inducing producers to supply more and consumers to reduce quantity demanded until a new equilibrium is reached (C1). 6(c): If price is held at the old level, quantity demanded exceeds quantity supplied, producing a shortage (M1). Buyers compete for limited meals, for example through queues or waiting time (A1). One valid non-price allocation method, such as first-come-first-served, rationing, or priority allocation, earns (A1).
Question 710 marks
7(a): GDP = C + I + G + (X − M) (M1). Net exports = 260 − 290 = −30 (A1). GDP = 620 + 180 + 210 − 30 = 980 billion, matching the nominal GDP shown (A1). 7(b): Real GDP = nominal GDP × 100 / GDP deflator (M1). Substitution: 980 × 100 / 105 (M1). Real GDP = 933.3 billion to one decimal place (A1). Correct units/rounding (A1). 7(c): One valid reason with explanation: for example, income may be distributed unevenly, so average real GDP per capita can rise while lower-income residents' real incomes fall or rise less (1+1); alternatively, GDP per capita does not fully reflect leisure, environmental quality, unpaid work, or access to public services, with a relevant explanation (1+1).
Question 88 marks
8(a): Required reserve = 10% × 10,000=1,000 (M1,A1). Maximum initial loan = 10,000−1,000 = 9,000(A1).8(b):Depositmultiplier=1/requiredreserveratio=1/0.10=10(M1).Maximumtotaldeposits=10,000 × 10 = $100,000 (A1). State that this is the total deposit expansion, including the original deposit, rather than an additional $100,000 on top (A1). 8(c): One reason and explanation, e.g. borrowers may keep some loan proceeds as cash, reducing redeposits and subsequent rounds of lending (M1); or banks may hold excess reserves / lack creditworthy borrowers, so actual lending is below the assumed maximum (A1). Question 914 marks
9(a): Multiplier k = 1 / (1 − MPC) (M1). k = 1 / 0.2 = 5 (A1). One assumption: prices are fixed over the relevant range; alternatively, no induced imports, taxes, saving changes beyond the MPC relationship, or capacity constraint (A1). 9(b): Lower investment reduces autonomous expenditure (M1); weaker export markets reduce exports and net exports (M1). In the aggregate expenditure model, planned expenditure falls, so firms experience unplanned inventory accumulation and reduce output (A1). Lower output reduces derived demand for labour and employment (A1). The initial spending fall can be multiplied through successive rounds of lower income and consumption, subject to leakages (C1). 9(c): For expansionary fiscal policy, a rise in government spending or a tax reduction increases planned expenditure and can raise output and employment, especially with spare capacity (M1,A1). The multiplier may make the effect larger than the initial injection, though imports, saving and taxation limit it (A1). Against: inflation has accelerated; if the economy is near capacity or supply constraints bind, extra demand can mainly raise the price level (M1,A1). Fiscal expansion may also worsen the budget balance, and its effects may arrive with a time lag (A1). Judgment: policy is appropriate only if the output gap is substantial and inflationary pressures are not mainly supply-driven; a targeted, temporary measure combined with monitoring or supply-side action is preferable (C1). Credit an alternative supported judgment.
Question 1014 marks
10(a): Street lighting is largely non-rival in consumption (1) and difficult to exclude non-payers from using (1). A provider cannot readily charge each beneficiary according to use (1), so individuals have an incentive to free-ride and understate willingness to pay; private provision may be below the socially efficient level (1). 10(b): Emissions impose an external cost on others, so without intervention private decision-makers do not bear the full social cost (M1). A per-unit tax raises the private cost of emitting or using fuel (M1), encouraging less driving, cleaner vehicles, or other substitution (A1). Lower emissions improve allocative efficiency if the tax brings private incentives closer to social costs (A1). The size of the reduction depends on price elasticity of demand / availability of substitutes / ability to alter travel behaviour (A1). 10(c): Efficiency argument: a tax can create an ongoing incentive to abate emissions and allow firms or drivers to choose the least-cost reductions; revenue can fund public transport or rebates (M1,A1). Equity concern: the tax may take a larger share of income from lower-income households, especially where they cannot avoid car use (M1,A1). Other valid concerns include difficulties measuring marginal external damage, congestion or emissions differing by location/time, effects on businesses, and acceptability. Evaluation: targeted rebates or improved public transport can address distributional effects while retaining the price signal; a tax is not automatically fair or perfectly efficient, and its merits depend on design and available alternatives (C1).
Question 1114 marks
11(a): Economy H gives up 120 / 60 = 2 thousand garments per additional thousand components (M1,A1). Economy R gives up 80 / 80 = 1 thousand garments per additional thousand components (M1,A1). R has the lower opportunity cost and therefore comparative advantage in components. Award the comparative-advantage identification within the final A1; do not award it for comparing absolute output alone. 11(b): If each economy specializes relatively more in the good with lower opportunity cost, combined output can rise (M1). Exchange allows each to obtain some of the other good and may permit consumption beyond its own production possibility frontier (A1). For components, mutually beneficial terms of trade must lie between the two opportunity costs: more than 1 and less than 2 thousand garments per thousand components (M1,A1). Reference to reciprocal specialization or gains from exchange (A1). 11(c): Consumers in H face a higher domestic price and generally lose consumer surplus; they may have fewer choices (M1,A1). Domestic component producers may expand output and gain producer surplus, and the government may receive tariff revenue if imports continue (M1,A1). However, consumers and downstream firms using components bear higher costs; protected output may be produced at higher opportunity cost, reducing gains from trade and creating a deadweight loss (M1,A1). Other valid points include retaliation, employment adjustment, infant-industry or strategic-industry arguments, and the possibility of revenue use for adjustment or training. Conclusion should weigh these effects: a broad or permanent tariff is difficult to justify solely on protection grounds; a temporary, targeted measure may be considered only where a clearly evidenced strategic or adjustment objective outweighs consumer and efficiency costs (C1).
Question 1214 marks
12(a): More consumers attract more restaurants and greater choice (M1); more restaurants in turn attract consumers, reinforcing the platform's user base (A1). Control of data, brand recognition, or high fixed costs can make it difficult for entrants to match the established platform's service or reach (M1,A1). These features can reduce competitive pressure and strengthen market power. 12(b): Short-run benefit: market power or scale economies may allow investment in technology, reliable delivery, or discounts that benefit consumers or restaurants (M1,A1). Possible longer-run concern: weaker competition can enable higher fees, lower service quality, reduced choice, or exclusion of rivals, harming consumers or restaurants (M1,A1). Accept another clearly explained, contrasting consequence. 12(c): Case for restriction: exclusive discounts may induce restaurants to avoid rival platforms; where a platform has substantial market power this can foreclose rivals, raise entry costs, and weaken competition (M1,A1). This can protect choice, innovation, and competitive pressure in the long run (A1). Case against: discounts can lower restaurant costs or consumer prices, reward volume, and reflect legitimate competition; banning them may reduce efficiency and consumer benefits (M1,A1). Evidence needed: platform market shares and durability, switching and multi-homing rates, discount terms and duration, rivals' ability to reach viable scale, actual price/quality effects, and whether the conduct prevents efficient entry (A1). Judgment: intervention is justified only if evidence indicates substantial foreclosure and likely consumer harm; a narrowly tailored restriction or monitoring may preserve pro-competitive discounts while addressing exclusion (C1).
Question 1320 marks
Candidates answer ONE alternative only; the assessed total for Question 13 is 20 marks. The two alternatives are not added together.
13 / Alternative 1 / (a): A monopolist faces the market demand curve and must lower price to sell additional units, so marginal revenue lies below price (M1,A1). Profit is maximised where marginal revenue equals marginal cost, provided the relevant conditions hold (M1). At that output, the demand price is above marginal revenue and hence above marginal cost in the standard case (A1). Restricting output relative to the competitive outcome can permit a higher price and create a welfare loss (A1).
13 / Alternative 1 / (b): If the cap is binding below the monopoly price, the firm charges the capped price (M1) and may expand output to the quantity demanded at that price, subject to capacity and cost conditions (A1). Profit normally falls relative to the uncapped monopoly outcome, though it need not disappear (A1). If set too low, the cap may reduce maintenance, investment, service quality, or even induce exit where revenue cannot cover relevant costs (A1).
13 / Alternative 1 / (c): Price discrimination means charging different prices to different buyers or for different units, not fully explained by cost differences, usually requiring market segmentation and limited resale (M1,A1). It can expand output for some consumers but may extract surplus; it harms competition/consumers if it excludes rivals or exploits groups with few alternatives (A1). Predatory pricing means pricing below an appropriate cost benchmark with the aim and likelihood of excluding rivals, followed potentially by recoupment after competition weakens (M1,A1). Low prices alone are not proof: the exclusion and likely longer-run harm must be evidenced (A1).
13 / Alternative 1 / (d): A cap can protect consumers quickly and constrain excessive prices where competition is weak (M1,A1). But the regulator needs reliable cost, demand and quality information; a poorly designed cap can distort investment, quality or entry (M1,A1). Competition enforcement can target exclusionary conduct and preserve price competition and innovation, but investigations may be slow and structural entry barriers can remain (M1,A1). A reasoned conclusion weighs the market's natural-monopoly features, evidence of consumer harm, regulator capability, and the ability to monitor quality; a carefully designed cap with periodic review and competition enforcement may be preferable to either instrument alone (C1). Credit a coherent alternative conclusion.
13 / Alternative 2 / (a): Factor endowment theory predicts that a country tends to export goods using its relatively abundant factor intensively and import goods using its relatively scarce factor intensively (M1,A1). If labour is relatively abundant and capital relatively scarce, labour-intensive products have a lower opportunity cost (M1,A1), supporting exports of those products and imports of capital-intensive products (A1).
13 / Alternative 2 / (b): Trade integration can widen markets, increase specialization and competition, and allow firms to exploit economies of scale (M1,A1). Foreign investment may bring capital, technology, management skills and access to international production networks, raising productivity (M1,A1). A limitation or risk, such as gains being concentrated, domestic firms being displaced, environmental damage, dependence on foreign firms, or technology spillovers failing to occur, earns (A1).
13 / Alternative 2 / (c): Economic growth is an increase in real output, commonly measured by real GDP or real GDP per capita over time (M1). Economic development is broader and concerns sustained improvement in material well-being, capabilities and quality of life (M1). GDP growth alone can conceal unequal distribution, poverty, environmental costs, health or education outcomes, and unpaid activity (A1,A1).
13 / Alternative 2 / (d): Education can improve skills and labour productivity, while transport infrastructure can lower business costs, connect workers to jobs and enable firms to access markets (M1,A1). These measures can support diversification, investment and more sustained gains (A1). However, access and quality may differ by income or region, so benefits can be uneven; education may take time to translate into suitable employment (M1,A1). Infrastructure and production can also create environmental or social costs, while trade shocks may harm particular workers and communities (A1). Judgment: investment can raise the potential for broadly shared development but cannot ensure it; complementary policies such as accessible training, social protection, competition, environmental safeguards and evaluation of distributional outcomes are needed (C1).