I have no idea how to do these plz help and plz make sure it’s right because I only have 5 questions and will mark brainiest:)

The diameter of a ball is 8 in. what is the volume of the ball? use 3.14 for pi. enter your answer as a decimal in the box. round only your final answer to the nearest hundredth.

What is the axis of symmetry of the function f(x)=-(x+ 9)(x-21)

Aword processing program requires a 7- digit registration code made up of the digits 1,2,4,5,6,7 and 9 each number has to be used and no number can be used mor than once how many codes are possible