Mathematics pls help me.

If 50% of a number is 14 then 100% of the number is

Answer this question only if you know the answer! 30 points and

Sara goes on a slingshot ride in an amusement park. she is strapped into a spherical ball that has a radius 3*10^2 of centimeters. what is the volume of air in the spherical ball? use this formula: volume of a sphere=4/3pi,r^3 , where r is the sphere’s radius.