According to the instructors in this unit, what is the proper length for making an impromptu speech?

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• In tandem skydiving, instructors must have at least 3 years of experience in the field, and should have a valid license. ( )
• In order to take helpful notes during class, it is important to understand your instructors' style of lecturing.
• So much so in fact, all the following topics are discussed among three instructors in this unit except for （）.