Perhaps trust in entropy is enough—in a life only long enough for 10^2 exhales, a pig would exhale 4g of CO2. Even if it were oxygen, and the classroom’s inhabitants managed to inhale all of that before it untransfigures, that’s .1g apiece among 40 students, and guaranteed to be well-mixed in molecule-sized pieces in the blood stream. So each student would lose thousands of red blood cells and have some extra load on their blood filtration organs, but not enough that anybody would be likely to notice a problem.
I think it was way less than 100 exhales, and the breaths may not have had time to travel away from the pig, especially if she could guarantee there’d be no wind. So maybe she knows how long something can safely be transfigured into a pig or a liquid, but has a simpler rule for the students on their first class.
Or maybe she could create a magical barrier around the pig so it was as safe as if it were in a glass box.
Perhaps trust in entropy is enough—in a life only long enough for 10^2 exhales, a pig would exhale 4g of CO2. Even if it were oxygen, and the classroom’s inhabitants managed to inhale all of that before it untransfigures, that’s .1g apiece among 40 students, and guaranteed to be well-mixed in molecule-sized pieces in the blood stream. So each student would lose thousands of red blood cells and have some extra load on their blood filtration organs, but not enough that anybody would be likely to notice a problem.
I think it was way less than 100 exhales, and the breaths may not have had time to travel away from the pig, especially if she could guarantee there’d be no wind. So maybe she knows how long something can safely be transfigured into a pig or a liquid, but has a simpler rule for the students on their first class.
Or maybe she could create a magical barrier around the pig so it was as safe as if it were in a glass box.