A jewelry maker purchased 20 inches of gold chain. She used 3 over 8 of the chain for a bracelet. How many inches of gold chain did she have left? ( Inches )

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.