4 Earnest Instructional Videos

By my way of thinking, there's nothing funnier than earnest videos that capture a moment in history when we were a little more naïve. I ripped the following four clips from various longer, instructional vids that came out in the 70s and 80s. It took a bit of time, but I think if you give them a click, you'll find it was time well spent. Enjoy and feel free to share, please.
1. Slips, trips, and falls
Can someone please tell me why there's a woman typing 500wpm non-stop in the background as our lovely host tries to explain how to avoid tripping in the office environment?
2. Interesting eye care models
I would have liked to have been at the casting call for this series of scenes.
3. A mouse in the house
This is an instructional video that explains what a computer mouse is and how it works. This particular mouse was the first ever shipped with a personal computer, the Xerox 8010 Star Information System in 1981. (Yes, predating Apple by a couple years.)
4. The acrobat!
I'm not sure why this woman doesn't just keep her pens closer to her keyboard, or put the phone down before reaching for that file...
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