This combined chart displays sales as steelblue bars and profit as a red line across 28 days, using a band scale for the x-axis and a linear scale for the y-axis. The code loads CSV data via `d3.csv`, converts numeric fields with unary plus operators, and renders the visualization with SVG. It constructs the bar layer with `selectAll('rect')` and the line path using `d3.line`, then adds axes through `d3.axisBottom` and `d3.axisLeft`. The chart highlights the relationship between daily sales volume and profit trends.