Smiling Face Part 1
A smiling face is drawn in an SVG using React and D3. The yellow circle forms the head, with two smaller circles for eyes and a D3 `arc` path for the mouth. The code uses React for component structure and d3.arc to define the mouth’s inner and outer radii and angles. The stroke width, eye offsets, and mouth dimensions are set as constants, and the SVG is rendered centered on a 960 by 500 canvas.