2024 CCEA A-Level Economics 4410 模擬試題連答案詳解

The short run is defined as the period of time in which at least one factor of production is fixed in supply, while other factors can still be varied; for a UK supermarket chain, an example of a fixed factor in the short run would be the physical floor space or warehouse capacity of an existing store, which cannot be changed quickly — in the short run, the firm can only respond to higher demand by varying a flexible factor such as labour (e.g. hiring more till staff or shelf-stackers) within that fixed space. The long run, by contrast, is the period of time long enough for ALL factors of production, including capital, to be varied — in this timeframe, the supermarket chain could build an entirely new, larger store or distribution centre, changing its fixed capacity itself rather than only the variable factors working within it. Answer: the short run is the period with at least one fixed factor (e.g. existing store floor space); the long run is the period in which all factors, including capital/store size, can be varied.

[1] short run correctly defined (at least one factor fixed); [1] valid example of a fixed short-run factor for a supermarket (store floor space, warehouse capacity, existing machinery/checkouts); [1] long run correctly defined (all factors variable); [1] valid example of a long-run adjustment (building a new store/distribution centre, or an explicit contrast that capital itself becomes variable). Full marks require both definitions AND at least one relevant example.

(a) Total revenue = price x quantity = £3.50 x 40,000 = £140,000. (b) Total variable cost = variable cost per unit x quantity = £2.10 x 40,000 = £84,000. (c) Total cost = total fixed cost + total variable cost = £28,000 + £84,000 = £112,000. (d) Profit = total revenue − total cost = £140,000 − £112,000 = £28,000 (a profit, since revenue exceeds cost). Answer: (a) £140,000; (b) £84,000; (c) £112,000; (d) £28,000 profit.

(a) [1] correct TR = £140,000. (b) [1] correct TVC = £84,000. (c) [1] correct TC = £112,000 (own figure rule: award if correctly calculated as fixed cost + candidate's own TVC from (b), even if (b) was wrong). (d) [2]: [1] correct method (TR − TC), [1] correct final answer £28,000 profit (own figure rule applies using the candidate's own TR and TC). No credit for a bare correct answer with no working shown, per the instruction to show workings.

(a) ATC = TC / Q at each output level: Q=100: £2,600/100 = £26.00. Q=200: £4,400/200 = £22.00. Q=300: £6,900/300 = £23.00. Q=400: £9,600/400 = £24.00. Q=500: £13,000/500 = £26.00. (b) Comparing these values, ATC falls from £26.00 at Q=100 to a minimum of £22.00 at Q=200, then rises again to £23.00, £24.00 and £26.00 at Q=300, 400 and 500 respectively — so ATC is minimised at an output of 200 units. Between Q=100 and Q=200, the firm is experiencing economies of scale: as output rises, ATC falls, meaning the firm is becoming more efficient, spreading its fixed costs over more units and/or benefiting from other scale efficiencies. Beyond Q=200, the firm experiences diseconomies of scale: as output continues to rise, ATC increases, suggesting the firm has grown too large to manage efficiently (e.g. rising coordination or communication costs), so this firm's short-run efficient scale of production is 200 units per week. Answer: (a) ATC = £26.00, £22.00, £23.00, £24.00, £26.00 respectively for Q=100 to 500; (b) ATC is minimised at Q=200 units (£22.00); economies of scale below this output, diseconomies of scale above it.

(a) [3]: 1 mark for each of two correctly calculated ATC values shown as working (award all 3 marks if at least 4 of the 5 values are correct; award 2 marks if 2-3 are correct; award 1 mark if only 1 is correct). All five correct values: £26.00, £22.00, £23.00, £24.00, £26.00. (b) [2]: [1] correctly identifies Q=200 (or £22.00) as the ATC-minimising output; [1] correctly explains economies of scale below and diseconomies of scale above this output, using the word 'economies'/'diseconomies' or an equivalent accurate explanation (own figure rule applies if part (a) contained an error).

Diagram description: draw price/cost on the vertical axis and quantity on the horizontal axis. Draw a downward-sloping demand curve, labelled AR (average revenue), and a second downward-sloping curve below and steeper than AR, labelled MR (marginal revenue) — MR is steeper than AR because, as a monopolist is a single price-setter facing the whole market demand curve, it must lower the price on ALL units sold (not just the extra unit) to sell one more unit, so each extra unit's marginal revenue falls faster than average revenue. Draw a U-shaped marginal cost (MC) curve and a U-shaped average cost (AC) curve sitting above it (with MC crossing AC at AC's minimum point). The profit-maximising output, Qm, is found where MC = MR (the standard profit-maximising rule, since a firm maximises profit by producing up to the point where the cost of producing one more unit exactly equals the revenue gained from selling it); from Qm, draw a vertical line up to the AR (demand) curve, and read the profit-maximising price, Pm, across to the vertical axis — Pm lies above MC at that output. Explanation: because the monopolist sets Qm where MC = MR (not where MC = AR/Price, as would occur under perfect competition), and because MR lies below AR at every output above zero, the resulting price Pm is higher, and the resulting output Qm is lower, than the price and output (Pc, Qc) that would occur under perfect competition, where firms are price takers and produce where P = MC. This gap between Pm and MC at the monopolist's chosen output represents the monopolist's ability to restrict output below the competitive level and charge a price above marginal cost, generating supernormal (abnormal) profit if Pm exceeds AC at Qm — profit that could persist in the long run in monopoly due to barriers to entry, unlike under perfect competition where supernormal profits are competed away. Answer: the monopolist restricts output to Qm (where MC=MR, below the competitive output) and charges Pm (read off the AR curve above Qm, above marginal cost), because it is a price-setter facing a downward-sloping demand curve with MR below AR, unlike a perfectly competitive firm which produces where P=MC.

3-level Level-of-Response: Level 1 (1-2 marks) — basic, partial diagram description (e.g. AR and MR only, or MC=MR rule stated without diagram detail); limited linkage to the comparison with perfect competition. Level 2 (3-4 marks) — reasonably complete diagram description (AR, MR, MC, AC curves all present and correctly ordered/shaped) with the MC=MR profit-maximising rule correctly applied to find Qm and Pm; some comparison with perfect competition. Level 3 (5-6 marks) — fully accurate, complete diagram description with all curves, correctly labelled profit-maximising output and price, AND a clear, explicit, well-explained comparison showing why monopoly output is lower and price higher than under perfect competition (P=MC benchmark), fluently written with accurate technical vocabulary throughout.

Data manipulation: the operating profit margin rose overall from 7.1% in 2020 to 9.0% in 2024, an absolute increase of 1.9 percentage points, which represents a proportionate increase of approximately 27% relative to its 2020 level ((9.0-7.1)/7.1 x 100 = 26.8%, rounding to about 27%). Trend description: the rise was not smooth or continuous — the margin increased from 7.1% (2020) to 7.6% (2021), then fell to 6.3% in 2022 (a fall of 1.3 percentage points from 2021, its lowest point across the whole period), before recovering strongly to 8.0% in 2023 and 9.0% in 2024, its highest point in the period. Answer: an overall rising trend from 7.1% to 9.0% (up 1.9 percentage points, around 27%), interrupted by a dip to 6.3% in 2022 before a strong recovery in 2023-2024.

[2] for absolute trend description: [1] correctly identifies the overall rise from 7.1% (2020) to 9.0% (2024); [1] correctly identifies the interruption/dip to 6.3% in 2022 as the lowest point, with recovery after. [2] for appropriate data manipulation/calculation: [1] correct calculation of the overall change (1.9 percentage point increase, or approximately 27% proportionate increase); [1] correct calculation of the 2021-2022 fall (1.3 percentage points) or an equivalent valid calculated figure drawn from the data. Marks for calculation require the actual calculated figure to be shown, not just a qualitative description.

Long-run average cost (LRAC) reflects the cost per unit when a firm is free to vary ALL its factors of production, including capital and the overall scale of the business, in order to find the most efficient scale of operation. Source C illustrates this directly: GreenValley Foods plc has invested in automated warehousing to reduce long-run average costs 'as output has expanded', and increasing the scale of its distribution network allowed it to 'negotiate lower per-unit prices from suppliers' — both are long-run decisions, since they involve changing the firm's capital (automated warehouse equipment) and its scale of operations, something only possible when no factor is held fixed. Short-run average cost (SRAC), by contrast, reflects the cost per unit when at least one factor (typically capital/the firm's scale) is fixed and the firm can only vary flexible factors such as labour. Source C also illustrates this: when GreenValley expanded into a new region, it had to 'hire and train additional temporary staff at short notice', which 'temporarily rais[ed] short-run average costs' — this is a short-run cost increase because it involves varying only labour quickly to respond to a new situation, before the firm's capital/systems in that new region have had time to reach their most efficient long-run scale. This distinction is directly reflected in Data Figure 2: the dip in operating profit margin to 6.3% in 2022 (down from 7.6% in 2021) is consistent with a temporary, short-run rise in average costs — such as the costs of hiring and training staff for regional expansion described in Source C — before the margin recovers strongly to 8.0% in 2023 and 9.0% in 2024, consistent with the firm reaching a more efficient long-run scale as its automated warehousing and expanded distribution network (also described in Source C) bring per-unit costs back down and below their earlier level. Answer: long-run average cost falls as ALL factors (including capital/scale, e.g. automated warehousing) are optimised, per Source C; short-run average cost temporarily rises when only variable factors (e.g. temporary staff) can be adjusted around a fixed scale, consistent with the 2022 profit margin dip in Data Figure 2, before long-run efficiencies restore and improve the margin by 2023-2024.

3-tier Levels-of-Response assessing AO1 (knowledge of short-run/long-run cost theory) and AO2/AO3 (application to Source C and Data Figure 2). Level 1 (1-3 marks): basic, undeveloped distinction between short run and long run, with little or no reference to the sources/data. Level 2 (4-6 marks): accurate distinction between short-run and long-run average cost, with some reference to Source C's examples (automated warehousing OR temporary staff) but limited or no linkage to Data Figure 2. Level 3 (7-9 marks): precise, accurate distinction fully applied to Source C (BOTH the automated warehousing/long-run example AND the temporary staff/short-run example), explicitly and correctly linked to the 2022 dip and subsequent recovery in Data Figure 2's profit margin data. No reference to the Source/data: cap at Level 1 (max 3 marks).

Evidence FOR characterising the market as an oligopoly: an oligopoly is typically defined as a market dominated by a small number of large firms with a high concentration ratio; using Data Figure 1, the four-firm concentration ratio (CR4) can be calculated as the combined market share of the four largest retailers by share — Tesco (27%) + Sainsbury's (15%) + Asda (13%) + Aldi (10%) = 65%. A CR4 of 65% is conventionally regarded as indicating a highly concentrated, oligopolistic market (a common benchmark is that a CR4/CR5 above roughly 60% suggests oligopoly), directly supporting Source A's claim that the combined share of the four largest retailers 'exceeded three-fifths' (60%) of the market. Source A also describes classic oligopoly behaviour: heavy use of non-price competition (loyalty schemes, exclusive own-brand ranges, online delivery investment) alongside price competition, consistent with firms in a concentrated market recognising their mutual interdependence and preferring to compete on factors other than price, where a price cut could provoke a damaging price war. Evidence AGAINST or QUALIFYING a simple oligopoly characterisation: Data Figure 1 also shows that no single firm has an overwhelmingly dominant share (the largest, Tesco, holds only 27%, well short of a monopoly position), and that a substantial combined 30% of the market is held by Aldi, Lidl, Co-op, Waitrose and other retailers, including two fast-growing discount chains (Aldi 10%, Lidl 8%) whose combined 18% share suggests the market retains meaningful contestability from firms outside the traditional 'Big Four'; Source A itself notes that 'switching between supermarkets is relatively easy' for consumers, which is a barrier-to-entry/contestability factor not typical of a highly closed oligopoly, and may constrain the pricing power the CR4 figure alone might suggest. A strong answer reaches a substantiated judgement — for example, that the UK grocery market shows clear structural features of an oligopoly (high CR4, non-price competition, interdependent pricing behaviour) but is more contestable than a 'textbook' rigid oligopoly, due to strong discount-retailer growth and low consumer switching costs. Answer: open evaluative response — the calculated CR4 of 65% and Source A's evidence of non-price competition support an oligopoly characterisation, but the discount retailers' growing combined share and easy consumer switching qualify how rigid or closed that oligopoly actually is.

3-tier Levels-of-Response assessing AO1 (knowledge of oligopoly/concentration theory), AO2/AO3 (application and analysis using Data Figure 1/Source A), and evaluation. Level 1 (1-4 marks): basic assertion that the market 'has a few big firms', no correct concentration ratio calculated, minimal use of the source/data. Level 2 (5-8 marks): a correct or near-correct CR4 calculation (65%, or a reasonable alternative such as CR3/CR5) linked to oligopoly theory, with some reference to Source A's non-price competition evidence; limited critical evaluation/qualification. Level 3 (9-12 marks): accurate CR4 calculation (65%) explicitly and correctly linked to oligopoly theory and Source A's evidence, PLUS a genuine critical evaluation/qualification (e.g. discount retailer growth, ease of switching) leading to a substantiated overall judgement. No use of the Source/data: cap at Level 1 (max 4 marks). No evaluation/qualification (one-sided): cap at Level 2 (max 8 marks).

Evidence that the CMA's decision was EFFECTIVE in protecting consumer welfare: Source B states the CMA found the merger 'would be likely to lead to a substantial lessening of competition, resulting in higher prices and reduced choice for shoppers' — by blocking it, the CMA directly prevented this predicted consumer harm from materialising in overlapping local areas and in national online/convenience markets; this is consistent with the CMA's statutory duty to protect consumer welfare from anti-competitive horizontal mergers, and blocking a merger between two of the 'Big Four' would have prevented CR4 in Data Figure 1 from rising even further, preserving more rivalry between the remaining large firms. Evidence QUALIFYING or LIMITING the decision's effectiveness: Source B notes the merging firms argued that 'greater scale would allow them to compete more effectively against online and discount rivals' — if blocking the merger left the two firms individually less able to achieve cost efficiencies (such as the economies of scale/lower supplier prices GreenValley achieved through growth, described in Source C) or to compete with fast-expanding discounters like Aldi and Lidl (whose combined 18% share is shown in Data Figure 1), consumers could arguably have lost out on potential lower long-run costs/prices that greater scale might eventually have passed on; additionally, blocking a single merger does not address the underlying high concentration already present in the market (CR4 of 65%, per Data Figure 1) — the CMA's intervention is necessarily reactive (assessing mergers as they are proposed) rather than a comprehensive solution to oligopoly-level concentration, meaning its effectiveness in protecting consumer welfare is limited to preventing further increases in concentration rather than reducing existing concentration. A strong answer reaches a substantiated judgement, for example that the CMA's decision was likely effective in preventing an immediate, clearly-evidenced reduction in competition in overlapping areas, but represents only a partial safeguard for consumer welfare given the market's already high pre-existing concentration and the unresolved question of whether blocked efficiency gains might otherwise have benefited consumers. Answer: open evaluative response — see markingScheme (Levels 1-3); credit any well-substantiated, balanced judgement grounded in Source B.

3-tier Levels-of-Response assessing AO1 (knowledge of competition policy/merger assessment), AO2/AO3 (application to Source B) and AO4 (evaluation/judgement). Level 1 (1-5 marks): general, undeveloped assertion (e.g. 'blocking mergers protects consumers'), minimal Source B reference, no evaluation. Level 2 (6-10 marks): accurate explanation of the CMA's reasoning (substantial lessening of competition) with clear Source B reference, but largely one-sided (either only benefits or only costs of the decision considered). Level 3 (11-15 marks): accurate, developed explanation of BOTH the consumer-protection benefits AND the limitations/costs of the decision, explicitly grounded in Source B (and, where used, Data Figure 1/Source C), reaching a clear, substantiated overall judgement on effectiveness. No use of the Source: cap at Level 1 (max 5 marks). Lack of significant balance: cap at Level 2 (max 10 marks).

QUESTION 6 indicative content: Arguments FOR organic growth being safer: organic growth (expanding by opening new stores/branches, developing new products, or growing sales within existing markets) allows a firm to expand at a controlled, manageable pace, funded from retained profit or modest borrowing, avoiding the very large debts or share issues often needed to finance a takeover; it avoids well-documented risks of mergers and acquisitions, such as cultural clashes between merging workforces, the complexity and cost of integrating different IT/management systems, and the risk of overpaying for a target firm (empirical studies of M&A frequently find a large proportion of mergers fail to create the shareholder value predicted at the time of the deal); organic growth also avoids competition authority scrutiny and the risk of a deal being blocked or delayed (as illustrated by cases such as the CMA's 2019 blocking of a proposed UK supermarket merger), which can waste significant management time and cost even if the deal ultimately proceeds. Arguments AGAINST/qualifying the statement: organic growth is typically much slower than growth via acquisition, meaning a firm risks losing market share or being left behind by faster-moving rivals in a fast-changing market (e.g. digital/online retail); acquisition can provide immediate access to new markets, technology, brands or skilled staff that would take years to develop organically, and can achieve cost-reducing economies of scale much more quickly; not all mergers fail — well-integrated acquisitions can create substantial value, and the 'riskiness' of M&A depends heavily on the quality of due diligence and post-merger integration management, not on the growth method itself being inherently unsafe. A high-level answer evaluates the relative importance of speed versus risk for different types of firm/market, and reaches a substantiated judgement (e.g. that organic growth is generally lower-risk but the 'safer' route is not universally true — it depends on the competitive urgency the firm faces and the quality of its acquisition strategy where relevant). QUESTION 7 indicative content: Arguments FOR competition policy being insufficiently tough: high concentration ratios persist in various UK markets (e.g. grocery retail, energy, banking), suggesting current merger control and monopoly regulation have not prevented significant market power from accumulating; the CMA can only investigate conduct or mergers it becomes aware of or that are referred to it, and remedies (such as blocking a merger, as in the 2019 supermarket case) are reactive rather than preventing dominance from building up through many smaller acquisitions or organic growth over time; fines for anti-competitive behaviour, while sometimes large in absolute terms, may be a small fraction of a dominant firm's annual profit, potentially providing insufficient deterrence. Arguments AGAINST/qualifying the statement: the CMA does actively intervene, as shown by real examples such as the 2019 merger block, demonstrating competition policy is not merely theoretical; UK/EU-derived competition law includes multiple tools beyond merger control, including prohibiting abuse of a dominant position and anti-competitive agreements (cartels), with substantial fines available (up to a percentage of global turnover); markets that appear concentrated are not necessarily uncompetitive if they remain contestable (e.g. low switching costs, growing discount retailer entry, as in the grocery sector), meaning high concentration alone does not prove policy failure. A high-level answer weighs the real deterrent and preventative effect of competition policy against its reactive limitations, reaching a substantiated judgement on whether it is 'not tough enough' overall or broadly effective with specific gaps. Answer: open evaluative essay for either Question 6 or Question 7 — see markingScheme (4-level grid); credit any well-substantiated, balanced judgement using accurate economic theory and real-world application.

4-level Level-of-Response grid assessing AO1 (accurate knowledge of relevant theory/policy), AO2 (application to real UK business/policy examples), AO3 (analysis/chains of reasoning), AO4 (evaluation and a substantiated judgement), plus QWC (clarity, structure, technical economics vocabulary). Level 1 (1-7 marks): largely descriptive, limited or inaccurate theory, little or no real-world application, no meaningful evaluation. Level 2 (8-15 marks): accurate core theory/knowledge present with some real-world application (e.g. a named example), developing analysis, but limited or one-sided evaluation. Level 3 (16-23 marks): accurate, well-applied theory with clear real-world examples, sound analytical chains of reasoning covering multiple points, and a developing but not fully substantiated evaluative judgement. Level 4 (24-30 marks): comprehensive, accurate theory fully applied to specific, correct real-world examples; sophisticated, multi-stranded analysis; a fully substantiated, well-reasoned evaluative judgement directly answering the question set; fluent, well-structured written communication with precise economics terminology throughout. Lack of significant balance (one-sided across the whole response): cap at Level 3 (max 23 marks). No real-world application/examples: cap at Level 2 (max 15 marks).