This bubble chart visualizes the relationship between average horsepower, average torque, and units sold for five fictional car makes. Each bubble’s x-position encodes horsepower, y-position encodes torque, and its radius scales with units sold using d3.scaleSqrt. The SVG rendering uses d3.axisBottom and d3.axisLeft for axes, while mouseover and mouseout events trigger a tooltip showing the make and units sold. Data is loaded asynchronously from a CSV file via d3.csv.