What two things balance to maintain the shape of a star?
o
a. pressure and gravity
b. orbiting and gravity
o
c. pressure and velocity

Plants can have a positive and negative effect on the rate of weathering

The oldest seafloor in the atlantic ocean is located closest to the edge of the continents. explain how this age can be used to figure out when north america first began to separate from europe

The plants growing on scotlands highland moors are a)mixed forestb)grasses and low shrubsc)evergreen treesd)palm trees and ferns