Spontaneous combustion is characterized by a self-starting fire.
Answer: Self-starting fire.
        
                    
             
        
        
        
The element used to make the first atomic bomb is uranium
        
             
        
        
        
Cytosine (C) and Guanine (G) are more steady under expanding heat since C and G have three hydrogen bonds while Adenine (An) and Thymine (T) have just two. The more hydrogen bonds there are, the more steady the nucleotides are. More bond dependability requires more warmth vitality to separate the securities, and since G≡C have more hydrogen securities than A=T, they are thusly more steady under expanding heat.
        
             
        
        
        
It's B
because ionic molecules are not soluble in oil
polar molecules are soluble in water
nonpolar molecules are not soluble in water
and metals are not soluble neither in water nor in oil