The original price of a ski jacket was $210. It was on sale at a 25% discount. Arianna had a coupon for an additional 10% off the sale price. What price did Arianna pay for the ski jacket?
A.
$141.75
B.
$136.50
C.
$157.50
D.
$147.50

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.