The flat surfaces of a 3D shape are called faces
To form a linear pair means that when added, they equal 180 degrees.
but if they have equal measures....180/2 = 90...then they would both equal 90 degrees.....and 90 degrees is a right angle.
So ABC and CBD are both right angles
We know, Volume of a Sphere = 4/3 πr³
V = 4/3 * π * (12.3)³
V = 4/3 * π * 1860.71
V = <span>2481.156π cm³
In short, Your Answer would be Option A
Hope this helps!</span>