Which of the following is an example of a constructive force? a. buildings collapse in an earthquake b. river erosion within the grand canyon's rock walls c. weathering of a mountain due to rain d. a volcano eruption i need quickly

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.

Cells destroy body cells infected by a virus or bacteria.

The transport tubes for food coming down the plants are called?