The sentence that is an example of formal speech is “Mr. Lee, your presentation was both informative and enjoyable.”
This is the speech used in formal contexts, this differs from informal speech because:
The second sentence “Mr. Lee, your presentation was both informative and enjoyable" is formal not only because the author used Mr. but also because there is formal vocabulary susch as informative and enjoyable.
Learn more about speech in: https://brainly.com/question/3743745
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