No, there was never a difference in the football size or regulations between the AFC and NFC. This would be too hard to regulate since the AFC and NFC teams play each other so often.
Allosteric regulation and Reversaeble regulation :)
A hamtet does not exist.
A problem is what exists when there is a difference between the current situation and the desired one.
There is no difference between "solipsism" and "solipcism"; they are likely just spelling errors of the same term, which refers to the philosophical idea that only one's mind is sure to exist or the view that the self is all that can be known to exist.
Any chemical difference exist.
The main difference is that a triangle rectangle cannot exist.
Regulation act
- protons are positive and neutrons are neutral- a small difference of mass exist
The longest time difference that can exist between two locations on Earth is 26 hours. This occurs when one location is at UTC14 and the other is at UTC-12.
ski jets dont exist
One is an Australian Marsupial (kangaroo); the other does not exist.
polarized