```html
<section>
  <h2>1/6 Scale Seastead Model — Displacement &amp; Froude-Scaled Full Size</h2>

  <h3>Given (Scale Model)</h3>
  <ul>
    <li>Main deck triangle side length: <strong>10 ft</strong> (above water; assumed to contribute <em>no</em> displacement)</li>
    <li>Number of legs/columns: <strong>3</strong></li>
    <li>Each leg: <strong>5 in</strong> diameter, <strong>6 ft</strong> long, angled <strong>45°</strong> out-and-down</li>
    <li>Submergence: <strong>60%</strong> of each leg length underwater (assumed along-leg submerged length)</li>
    <li>Water density assumed: <strong>seawater</strong> ≈ <strong>64 lb/ft³</strong> (≈ 1025 kg/m³)</li>
  </ul>

  <h3>Key Assumptions</h3>
  <ul>
    <li>Only the submerged portions of the 3 cylindrical legs displace water.</li>
    <li>The 45° angle does not change displaced volume if “60% underwater” refers to submerged <em>length along the cylinder</em>.</li>
    <li>Static target weight equals buoyant force (i.e., equals displaced water weight) for the stated floating condition.</li>
  </ul>

  <h3>Calculations (Scale Model)</h3>
  <ul>
    <li>Leg diameter: 5 in = <strong>0.4167 ft</strong>; radius r = <strong>0.2083 ft</strong></li>
    <li>Cross-sectional area per leg: A = πr² = π(0.2083)² = <strong>0.1364 ft²</strong></li>
    <li>Submerged length per leg: 0.60 × 6 ft = <strong>3.6 ft</strong></li>
    <li>Displaced volume per leg: V<sub>leg</sub> = A × L = 0.1364 × 3.6 = <strong>0.491 ft³</strong></li>
    <li>Total displaced volume (3 legs): V = 3 × 0.491 = <strong>1.474 ft³</strong></li>
    <li>Displaced water weight / buoyant force: W = 64 × 1.474 = <strong>94.3 lb</strong></li>
    <li>Displaced water mass (seawater): 1.474 ft³ = 0.0417 m³ → m ≈ 1025 × 0.0417 = <strong>42.7 kg</strong></li>
  </ul>

  <h3>Froude (Geometric) Scaling to Full Scale</h3>
  <p>
    Scale ratio (full/model) is <strong>&lambda; = 6</strong>.
    Under Froude scaling with the same fluid density:
    <strong>lengths scale as &lambda;</strong> and <strong>displacement/weight scales as &lambda;³</strong>.
  </p>

  <h3>Full-Scale Dimensions (Feet)</h3>
  <ul>
    <li>Main deck triangle side length: 10 ft × 6 = <strong>60 ft</strong></li>
    <li>Leg length: 6 ft × 6 = <strong>36 ft</strong></li>
    <li>Leg diameter: 5 in × 6 = 30 in = <strong>2.5 ft</strong></li>
    <li>Submerged leg length (60%): 0.60 × 36 = <strong>21.6 ft</strong></li>
  </ul>

  <h3>Full-Scale Displacement &amp; Target Weight</h3>
  <ul>
    <li>Total displaced volume scales by &lambda;³ = 216:
      V<sub>full</sub> = 1.474 × 216 = <strong>318.4 ft³</strong>
    </li>
    <li>Buoyant force / supported weight:
      W<sub>full</sub> = 94.3 × 216 = <strong>20,377 lb</strong>
      (≈ <strong>10.19 short tons</strong>)
    </li>
    <li>Displaced water mass (seawater):
      318.4 ft³ = 9.015 m³ → m ≈ 1025 × 9.015 = <strong>9,240 kg</strong>
    </li>
  </ul>

  <h3>Summary Table</h3>
  <table border="1" cellpadding="6" cellspacing="0">
    <thead>
      <tr>
        <th>Item</th>
        <th>Scale Model (1/6)</th>
        <th>Full Scale (1/1)</th>
      </tr>
    </thead>
    <tbody>
      <tr>
        <td>Triangle side length</td>
        <td>10 ft</td>
        <td>60 ft</td>
      </tr>
      <tr>
        <td>Leg diameter</td>
        <td>5 in (0.4167 ft)</td>
        <td>30 in (2.5 ft)</td>
      </tr>
      <tr>
        <td>Leg length</td>
        <td>6 ft</td>
        <td>36 ft</td>
      </tr>
      <tr>
        <td>Submerged leg length (60%)</td>
        <td>3.6 ft</td>
        <td>21.6 ft</td>
      </tr>
      <tr>
        <td>Total displaced volume (3 legs)</td>
        <td>1.474 ft³</td>
        <td>318.4 ft³</td>
      </tr>
      <tr>
        <td>Displaced water weight / buoyant force (seawater @ 64 lb/ft³)</td>
        <td>94.3 lb</td>
        <td>20,377 lb</td>
      </tr>
      <tr>
        <td>Total target weight to float at stated submergence</td>
        <td>94.3 lb</td>
        <td>20,377 lb</td>
      </tr>
    </tbody>
  </table>

  <p>
    If you want, I can redo the numbers for <strong>freshwater (62.4 lb/ft³)</strong> or if “60% underwater”
    means <strong>60% of the leg’s vertical projection</strong> rather than 60% of its length.
  </p>
</section>
```