Suggested approach: It’s a question of how many bits are used to store data:
Float is always 32-bit,
Double is always 64-bit, and
CGFloat is either 32-bit or 64-bit depending on the device it runs on, but realistically it’s just 64-bit all the time.
For bonus points, talk about how Swift 5.5 and onwards allows us to use
Estimated difficulty: Easy
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