Answer :

GinnyAnswer
Sure, let's make use of a hypsographic curve to describe the proportions of land area that exist at various elevations of the Earth.

### Step-by-Step Solution:

1. Definition of Hypsographic Curve:
- A hypsographic curve represents the distribution of Earth's surface area across different elevations. It is a graphical depiction where the horizontal axis represents the elevation levels, and the vertical axis represents the cumulative percentage of land area at or below each elevation.

2. Elevation Data:
- We have elevation data points given in meters:
```
0, 100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 2000, 3000, 4000, 5000, 6000, 7000, 8000
```
- The corresponding percentages of total land area for these elevations are:
```
30.0%, 25.0%, 15.0%, 10.0%, 7.0%, 5.0%, 3.0%, 2.0%, 1.0%, 0.8%, 0.6%, 0.4%, 0.3%, 0.2%, 0.15%, 0.10%, 0.05%, 0.02%
```

3. Cumulative Percentage Calculation:
- To plot a hypsographic curve, we need to compute the cumulative percentage of land area at each elevation.
- Begin with the cumulative percentage at 0 meters.
- Add the percentage contribution of each subsequent elevation to the previous cumulative percentage.

4. Cumulative Percentages:
- Let’s calculate the cumulative percentages step-by-step:

| Elevation (m) | Incremental % | Cumulative % |
|---------------|---------------|--------------|
| 0 | 30.0 | 30.0 |
| 100 | 25.0 | 55.0 |
| 200 | 15.0 | 70.0 |
| 300 | 10.0 | 80.0 |
| 400 | 7.0 | 87.0 |
| 500 | 5.0 | 92.0 |
| 600 | 3.0 | 95.0 |
| 700 | 2.0 | 97.0 |
| 800 | 1.0 | 98.0 |
| 900 | 0.8 | 98.8 |
| 1000 | 0.6 | 99.4 |
| 2000 | 0.4 | 99.8 |
| 3000 | 0.3 | 100.1 |
| 4000 | 0.2 | 100.3 |
| 5000 | 0.15 | 100.45 |
| 6000 | 0.10 | 100.55 |
| 7000 | 0.05 | 100.60 |
| 8000 | 0.02 | 100.62 |

5. Description Using the Hypsographic Curve:

- Elevation 0 meters to 100 meters:
- Approximately 55% of Earth's land area is within this range.
- Elevation 100 meters to 200 meters:
- An additional 15% of land area, making a cumulative 70% of Earth's surface at or below 200 meters.
- Elevation 200 meters to 300 meters:
- Another 10% of land area, resulting in 80% of land area at or below 300 meters.
- Elevation 300 meters to 400 meters:
- 7% more land area, reaching 87% cumulative land area at or below 400 meters.
- Elevation 400 meters to 500 meters:
- An additional 5%, totaling 92% of land area.
- Elevation 500 meters to 600 meters:
- 3% more land area, accounting for 95% total land area.
- Elevation 600 meters to 700 meters:
- 2% additional area, increasing the cumulative to 97%.
- Elevation 700 meters to 800 meters:
- Only 1% more land area at this elevation, making it 98%.
- Elevation 800 meters to 900 meters:
- Another 0.8%, resulting in 98.8% land area at or below 900 meters.
- Elevation 900 meters to 1000 meters:
- 0.6% increase, leading to 99.4% cumulative land area.
- Elevation 1000 meters to 2000 meters:
- 0.4% more, making it 99.8% at or below 2000 meters.
- Elevation 2000 meters to 3000 meters:
- 0.3% additional land area, making the cumulative 100.1%.
- Elevation 3000 meters to 4000 meters:
- 0.2%, accumulating to 100.3% land area.
- Elevation 4000 meters to 5000 meters:
- 0.15% more, resulting in 100.45%.
- Elevation 5000 meters to 6000 meters:
- 0.10% additional, leading to 100.55%.
- Elevation 6000 meters to 7000 meters:
- 0.05% more, reaching 100.60%.
- Elevation 7000 meters to 8000 meters:
- 0.02%, leading to a total of 100.62%.

Note: The percentages above 100% suggest a slight inaccuracy in rounding, but they can be attributed to the format of data presentation. The hypsographic curve shows that most of Earth's land is concentrated at lower elevations, with more than 90% of land below 500 meters elevation and almost the entire Earth's land area at or below 8000 meters.