A reusable scatter plot built with the reusable chart pattern displays the Iris dataset from Curran's Gist repository. It uses `d3.scaleLinear`, `extent`, and `axisBottom`/`axisLeft` for axes, with the chart configured via chainable methods for width, height, margin, and data accessors. The plot responds to data updates by joining circles to the DOM, rendering petal length against sepal length with steelblue points at 5-pixel radius and 0.7 opacity.