O Level Geography Practice Paper 1

TuitionGoWhere Practice Paper - Geography O-Level (Answer Key)

Topic: Map, Graph & Data Skills
Version: 1 of 5

Section A: Data Collection and Representation

1. (a) [1 mark]

• Line graph.
• Accept: Scatter graph (if trend line is mentioned), but Line graph is standard for continuous change over distance.

1. (b) [1 mark]

• Line graphs are suitable for showing continuous data / trends / changes over a continuous variable (distance).
• Must mention: trend, continuous nature, or relationship between two continuous variables.

1. (c) [2 marks]

• Use a dual-axis graph (compound bar chart or line graph with two y-axes).
• One y-axis for velocity (e.g., left side) and one y-axis for pebble length (e.g., right side).
• Use different colors/styles (e.g., line for velocity, bars for pebble length) and a clear legend.
• 1 mark for method (dual axis/compound), 1 mark for clarity (legend/labels).

1. (d) [1 mark]

• Wind affecting the float (pushing it faster/slower than water).
• Human reaction time error with the stopwatch.
• Float getting stuck on rocks/vegetation.
• Any valid source of error.

1. (e) [1 mark]

• Take multiple readings at each site and calculate the mean.
• Use a flow meter instead of a float (more precise instrument).
• Ensure the same distance is used for timing at all sites.

1. (f) [2 marks]

• Working: $(0.75 + 0.80 + 0.95 + 0.82 + 0.78) \div 5$
• Sum = $4.10$
• Mean = $4.10 \div 5 = 0.82$
• Answer: 0.82 m/s
• 1 mark for correct sum or setup, 1 mark for correct final answer.

1. (g) [2 marks]

• River velocity is typically fastest in the center/deepest part of the channel due to less friction with the bed and banks.
• Readings near the banks are slower due to higher friction.
• Therefore, 0.95 is likely the true maximum velocity, while the lower readings near banks are not anomalies but expected variations; however, if the aim was to measure average cross-section velocity, mixing center and bank readings without weighting creates an inaccurate mean.
• Accept: Explanation of friction/depth affecting velocity.

Section B: Statistical Analysis and Interpretation

2. (a) [1 mark]

• Data: 1, 2, 1, 2, 1 $\rightarrow$ Ordered: 1, 1, 1, 2, 2
• Median: 1

2. (b) [2 marks]

• Data: 3, 3, 4, 3, 3
• Working: $(3+3+4+3+3) \div 5 = 16 \div 5$
• Answer: 3.2

2. (c) [3 marks]

• Area Y has significantly higher environmental quality scores than Area X.
• Example: Noise levels in Area Y are 4-5 (Excellent/Good), while Area X are 1-2 (Poor).
• Example: Litter scores in Area Y are 4-5, while Area X are 1-2.
• 1 mark for general comparison, 2 marks for specific data references.

2. (d) [3 marks]

• Data: 1, 1, 1, 1, 2
• Weights: Scores 1-2 get weight x2.
• Calculation:
  • Four scores of 1: $4 \times (1 \times 2) = 8$ ? No, the weight applies to the score or the count?
  • Clarification of Template Method: Usually, weighted score = $\sum (\text{Frequency} \times \text{Weight})$. Or $\sum (\text{Score} \times \text{Weight Factor})$.
  • Let's assume the prompt implies: Value $\times$ Weight.
  • Score 1 (Weight 2): $1 \times 2 = 2$. There are four 1s. $4 \times 2 = 8$.
  • Score 2 (Weight 2): $2 \times 2 = 4$. There is one 2. $1 \times 4 = 4$.
  • Total = $8 + 4 = 12$.
  • Alternative Interpretation: If weight is applied to frequency:
    • Freq of 1-2 is 5. Weight 2. Total = 10.
  • Standard Geography Fieldwork Method: Usually, you sum the scores. If weighted, you multiply the score by a factor.
  • Let's stick to the simplest interpretation of "Weighted Score" in O-Level context:
  • Scores: 1, 1, 1, 1, 2. All fall in "1-2" category.
  • Weight for this category is x2.
  • Sum of raw scores = $1+1+1+1+2 = 6$.
  • Weighted Sum = $6 \times 2 = 12$.
  • Or: If the weight replaces the score:
  • Score 1 becomes 2. Score 2 becomes 2.
  • $2+2+2+2+2 = 10$.
  • Marking Note: Accept 10 or 12 if working is shown clearly. The key is applying the weight consistently.
  • Preferred Answer: 10 (If weight replaces the value for severity) or 12 (If weight multiplies the value). Let's provide 10 as the "Severity Index" approach often used in EQS.
  • Revised Working for 10: All 5 readings are in the 1-2 range. Weight is 2. $5 \text{ readings} \times 2 = 10$.

2. (e) [4 marks]

• Strength: Allows for quick comparison of multiple factors; quantifies subjective opinions (makes qualitative data quantitative); easy to administer.
• Limitation: Subjective/Biased (different people have different standards for "clean" or "quiet"); small sample size may not be representative; does not explain why the score is low.
• 2 marks for strength (1 for point, 1 for explanation), 2 marks for limitation (1 for point, 1 for explanation).

2. (f) [2 marks]

• Use a particulate matter sensor (PM2.5/PM10 monitor).
• Use a gas sensor (e.g., for $CO_2$, $NO_2$, $SO_2$).
• Must be a quantitative instrument, not a survey.

Section C: Map and Graph Interpretation

3. (a) [2 marks]

• Rainfall is higher on the West Coast (>2500mm) and lower on the East Coast (<1000mm).
• Rainfall decreases from West to East across the island.
• 1 mark for identifying high/low areas, 1 mark for the gradient/direction.

3. (b) [2 marks]

• April (250) + May (300) + June (320).
• $250 + 300 + 320 = 870$.
• Answer: 870 mm.

3. (c) [2 marks]

• Highest: 320 mm (June).
• Lowest: 180 mm (February).
• Range: $320 - 180 = 140$ mm.
• Answer: 140 mm.

3. (d) [3 marks]

• Prevailing winds blow from the West (sea) towards the land.
• Moist air is forced to rise over the central mountain range (Orographic uplift).
• Air cools, condenses, and rains on the Windward side (West/Station P).
• Air descends on the Leeward side (East/Station R), warms up, and holds more moisture (Rain Shadow effect), resulting in less rain.
• 1 mark for prevailing wind/uplift, 1 mark for condensation/rain on windward, 1 mark for rain shadow/leeward dryness.

3. (e) (i) [1 mark]

• Multiple line graph (or Compound line graph).
• Accept: Grouped bar chart.

3. (e) (ii) [2 marks]

• Pie charts show parts of a whole (percentages/proportions) for a single point in time or category.
• They cannot effectively show trends over time (months) or compare multiple variables (3 stations) across 12 time periods simultaneously.
• 1 mark for "parts of a whole" limitation, 1 mark for "cannot show trends/time series".

3. (f) [3 marks]

• No / Insufficient.
• Reason 1: Only one year of data (or unspecified duration) is shown; climate requires long-term averages (usually 30 years).
• Reason 2: Temperature data is missing; monsoon climates are defined by both rainfall and temperature patterns (or wind direction).
• Reason 3: Data from only one station (P) is insufficient to define the climate of the whole region/island.
• 1 mark for judgment, 2 marks for valid reasons.