Three static rectangles are appended to an SVG as placeholders for a bar chart, with each rectangle sized at 300 by 300 pixels. The chart reads population data from `data.csv`, converting values to actual populations by multiplying by 1,000. It uses `d3.csv` to load the data and `select` and `selectAll` from D3 v5 to manipulate the SVG elements. The rendering logic does not map data values to bar heights or widths, leaving the visualization incomplete.