This scatterplot is made with d3.js and SVG - For the canvas tutorial it is now your job to turn this scatterplot into one uses canvas for the visual part (the drawing of the circles). You can still use d3’s helper functions for things such as scales, d3.select, etc.
See the other two levels here: Medium level and Extreme level
If you’re completely stuck (and please, for your own benefit, only then) you can look at the solution here
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