The cell membrane allows only water passes through therefore the membrane is what

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.

Select all the correct answers. which statements fail to meet the requirements of a scientific claim? a). in the final 100 meters of a 10,000-meter race, an athlete's speed is more strongly related to anaerobic efficiency than to aerobic efficiency. b). flowers that reflect the most ultraviolet light are more likely to attract bees and other pollinators than flowers that reflect less ultraviolet light. c). the evidence supporting newton's laws of motion was accurate in newton's time, but the universe operates differently today. d). even though evidence indicates that the solar system's planets follow elliptical paths, copernicus's model involving circular orbits is true.

How does this procedure serve as a method of birth control?