Yes you'll find that any testable definition of AGI that has not been passed yet would be unpassable for a big chunk of the human population.
In other words, General, Artificial and Intelligent have been passed. That's why a few papers/researchers opt to call these models "General Artificial Intelligence" instead
Yes, but humans as a group can do it. An AGI needs to show a similar number of AGIs can do the same given the same starting template.
The AGI will need to look at all of the tasks written, determine what the success criteria is, and then combine that that into a single set of answers. With the instructions in human-readable form, not machine readable. It can use as many or as few AGIs as it needs to accomplish this.
It's the same as if we gave these instructions to a human with sufficient skill and resources to delegate.