Exercises
Short interactive exercises for each Part, with the same examples, numbers and terms as the slides. Each one teaches one idea: try it, read the feedback, and try again if you want to. Allow about 20 to 25 minutes per Part.
Everything runs in your browser. There is no account, and nothing you enter leaves this page. Your progress is stored only in this browser, so it does not follow you to another device. Three points means right the first time, two means right after a retry, and one means you looked at the answer.