Challenge 1: A Four-Bullet Progressive Reveal — Solution Walkthrough

Setup: 4 bullet points, each set to Entrance > Fade In, trigger set
to On Click.

What happens during the live presentation:

The slide initially appears with NONE of the four bullets visible.
Each click the presenter makes reveals exactly one more bullet,
fading it in — click once for bullet 1, click again for bullet 2, and
so on, until all four are visible after the fourth click. Nothing
appears automatically; every single bullet's appearance is tied
directly to the presenter physically clicking (or pressing a key/
clicker) to advance.

Why On Click is correct here, not After Previous:

On Click puts the PACING of the reveal entirely under the presenter's
own control — each bullet appears exactly when the presenter is ready
to discuss it, which could be a few seconds or a few minutes after the
previous one, depending entirely on how much the presenter has to say
about each point. After Previous, by contrast, would make each bullet
appear automatically, timed relative to the previous animation
finishing — completely disconnected from whatever pace the presenter
is actually talking at. For content the presenter is actively
explaining live, On Click is what lets the slide's visual reveal stay
in sync with the spoken explanation; After Previous is better suited
to a slide with no live presenter control at all (e.g. part of an
unattended, self-running sequence).

WHY THIS WORKS AS AN ANSWER
------------------------------
This is exactly the "genuinely useful case" this chapter describes:
using animation specifically to prevent the audience from reading
ahead of the speaker, which only works if the reveal's timing is tied
to the presenter's own pacing (On Click) rather than running on a
fixed automatic schedule.