Answer:
The volume of a ball that is 24 cm across is :
d). v = four-thirds pi 12 cubed
Explanation :
Ball is a sphere and volume of sphere is given by :

r = radius of ball

r = 12 cm
Volume is :

Effective collisions are those that result in a chemical reaction. In order to produce an effective collision, reactant particles must possess some minimum amount of energy. This energy, used to initiate the reaction, is called the activation energy.
Answer:
In first shell duplet rule is applied because first shell contains maximum 2 electrons
Explanation: