No issues to report yet, but I'm blown away by how C# has something for everyone. I was not expecting SQL queries in the regular programming syntax. Very creative. Any typos will be noted below.

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The sentence starting:

Copy the program you build for Exercise 2

should read:

Copy the program you built for Exercise 2

Note: Since the user created the program in a previous exercise, it is most appropriate in this kind of technical context to use "built" to refer to the past tense, as opposed to the more literary use of present tense to refer to the past.

As I come back to this a year or so later, I have to admit that this isn't all too concerning.