Sea floor spreading adds more crust to the ocean floor and at the same time older strips of rock move outward from either side of the ridge.
        
             
        
        
        
Answer:
I think I'll pick both.
Uk has a lower rate in sucide prevention than in the USA. It also has better social welfare. But Uk's price for a living is more higher than the USA. But USA has 50 states while the UK has is one whole state with 4 different
countries. The USA does not have a Tribunal System. USA has specific courts for bankruptcy and etc.
Hoped this helped!
 
        
             
        
        
        
the first plants and anthropodes appear on land approximately about 470 million years ago