measuring biodiversity in a community can ecologists predict the stability of an ecosystem. more biodiverse communities can make ecosystems more resilient to changes from natural or human origin. calculate the simpson's diversity index for a community with the following species distribution:
81 pine trees
19 oak trees
10 maple trees
a) 0.22
b) 0.42
c) 0.58
d) 0.81

It depends on the surface of the levels. the rougher the surface, the greater is the frictional force. for rougher surfaces, you would need to exert greater force to move the object. the concept is that, you must overcome the frictional force in order to bring the object into motion. this is the reason why we add lubricants to the joints so they could easily move. this answer was on