Scaling circle size with interpolate in Mapbox GL JS and React based on data – how to?

I am using mapbox in order to show a map in which the size of the circles is according to the amount in each country
But I couldn’t understand howyour text to use interpolate (expression) and the circles appear the same size.

map.current.on("load", () => {
      map.current.addSource("Amount", {
        type: "geojson",
        data: data,
      });

      map.current.addLayer({
        id: "amount-circles",
        type: "circle",
        source: "Amount",
        layout: {},
        paint: {
          "circle-color": [
            "match",
            ["get", "Country"],
            "Egypt",
            "#fbb03b",
            "Algeria",
            "#223b53",
            "Russia",
            "#e55e5e",
            "United Kingdom",
            "#3bb2d0",
            /* other */ "#ccc",
          ],
          "circle-opacity": 0.75,
          "circle-radius": [
            "interpolate",
            ["linear"],
            ["get", "Amount"],
            6,
            10,
            8,
            20,
          ],
        },
      });
      
    });

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