This example visualizes student performance by comparing subject-specific marks against total marks. It displays two scatter plots side by side: one for Maths versus total marks and another for English versus total marks. Using D3.js v6 with SVG rendering, the code defines a reusable `scatterPlot()` function that configures scales, axes, and circle marks. Data is loaded from a CSV file via `d3.csv` from a GitHub gist, with the x-axis key configurable between different subjects. The reusable function pattern allows both charts to share identical styling and features.