Hydrogen atoms are compressed
together by the enormous gravitational force
of the sun, causing them to fuse int a helium atom (which is heavier than
hydrogen), subatomic particles and enormous
release of atomic energy. The attached
picture shows the sequence of the main reaction
at the core of the sun. 
 
        
             
        
        
        
Oxygen-16 and Carbon-12 are stableisotopes of elements O and C respectively. Hence, they do not have half-lives. But Carbon-14 andUranium-238 are radioactive isotopes. Among them Carbon-14 has relatively short half-life as about 5730 years while Uranium-238 has a long half-life as about 4.5 billion years.
Answer is. uranium-238
        
             
        
        
        
Answer:
Just before the cat drops, it was stationery. Therefore it has energy of position called  potential energy.As it drops, the Gravitational potential energy is converted to Kinetic Energy,The conversion mid- air is P.E to K.E to P.E to K.E to P.E to K.E, until it touches the ground. As it touches the  ground all the energy is converted to P.E energy of position.
As it runs after mouse the P.E is converted back to Kinetic , energy of motion. As it feeds on the mouse , the chemical energy obtained  as protein from mouse meat.This is later converted back to Mechanical energy as (kinetic and Potential  energy)   in the cat.
Explanation:
  
        
                    
             
        
        
        
What is soft layer of earth that has convection currents and causes plates to move
        
             
        
        
        
A "ring of Life" is more appropriate to describe the relationship between archaea, bacteria, and eukaryotes than a “tree of life “, because each group of single-celled prokaryotic organisms produces something that is a necessity to another group of single-celled prokaryotic organisms. so therefor it is not like a tree of life which is more of a hierarchy than an everyone, and everything is equal Ring of Life.