Boy's hanging on to that baloon art with nothing but just his fists, he must be some kind of gorilla genjin because that's some kinda grip strength
It's the same as hanging on to a bar when doing pull-ups. Not really that hard, unless you are unusually big. Which Yutaka isn't.
I see you aren't familiar with school administrators.
Now that I'm no longer working at school, I would like to wish school administrators to suffer for everything they do. They do not do a single good thing for the school.
Yes, nice catch - the school administrator is finishing her train of thought with the end of his own lecture in a slightly different interpretation. I couldn't think of any way to emphasize this without an actual TN note, and as you've probably noticed we try to avoid those unless it's truly whaaaat? like the 'good at math' thing so just want with 'smoothly finishing her thought.'
If I was a mangaka, I would make it a double speech balloon - once for the school administrator, and once for the student's train of thought.
TBF this would be like tackling someone down and pressing them on the floor because they won't stop following and pestering you, if your so bothered then you should go to a teacher and have to kicked off school grounds or something.
So, a perfectly normal thing children do all the time. As if teachers would ever help you, and not the bullies.
Erm, actually that amount of balloons cant lift up even a small child ☝️🤓
Well, they are shown previously as holding up when a sporty dragon-girl is hanging on the installation.
As for lifting power, let's generously assume the ball is 3 meters in radius. That's 4 /3 *3.14 * (3^3), or about 122.4 m^3.
Air is 1.29 kg /m^3, hydrogen is about 0.09 kg / m^3. So that's about 1.2 kg of lifting power per m^3. Which means that generously-sized ball can lift about 146 kilograms of students (rounded down to account for balloon material), or 2-3 students, depending on how heavy they are.