This is because the material the ballon is made of is shaped differently.
The ballon will stretch and try to achieve a perfect round shape, but can not due to limitations in the way the ballon is made.
One can however buy balloons that are almost perfectly round when inflated.
it is perfectly round.
A long balloon typically holds more air than a round balloon due to its shape and design, which allows for increased volume capacity. The elongated shape of a long balloon allows it to expand more when filled with air compared to a round balloon.
When you blow air into a deflated balloon, the pressure from the air molecules pushes against the walls of the balloon, causing it to inflate and take on a round shape. The elastic material of the balloon allows it to expand and hold the air inside, maintaining its round shape until the pressure inside and outside the balloon equalizes.
yes
Yes
Assuming the balloon is perfectly spherical and that the 12" you state refers to the diameter of the balloon then it is obviously 6". If you can't assume any of the above then your question cannot be answered.
yes
pooey in the looey
Is a circle.
A sphere.
A circle or a sphere
Nobody's head is perfectly round. It is a free-form shape. Everybody's is a different shape.