Pauli exclusion principal says no two electrons can have same set of quantum number since for our distant universe three such electrons exist hence the correct answer for this is 3.
since we have 3 spin quantum number the configuration will be 1s3 2s3 2p2.
A noble gas has all orbital filled, first noble gas will have configuration 1s3 2s3 2p6 which means that its atomic number is 3+3+6 = 12
Ball bounces because of the difference in the air pressure on the outside of the ball, and opposite the point of impact, and the pressure inside of the ball. This means that the inside of the ball now has less space to contain the air molecules contained inside the ball, increasing the pressure inside the ball.