- If the abundance of the first isotope is 68.037%, then the abundance of the second isotope is 100%-68.037%.
 
Substituting into the atomic mass formula,

 
        
             
        
        
        
Answer: Option (d) is the correct answer.
Explanation:
In winter's, temperature of atmosphere is low and due to this molecules of air present in the tire come closer to each other as they gain potential energy and loses kinetic energy.
Hence, air pressure decreases and there is need to fill more air in the tire.
Whereas is summer's, temperature is high so, molecules of air inside the tire gain kinetic energy and move rapidly from one place to another due to number of collisions. So, air pressure increases and there is no need to fill more air inside the tire. 
Thus, we can conclude that the temperature is lower, so the air inside the tires contracts.
 
        
                    
             
        
        
        
Since 1mL=1cm^3 the wood would sink due to it being more dense. I.e. 0.95>0.88
        
                    
             
        
        
        
Answer:
Decomposition or cracking
Explanation:
In a decomposition or cracking reaction, a single compound produces two or more simpler substances. 
It involves the formation of two or more products from a single reactant. 
   A →  B + C 
A is the single reactant
B and C are the products
The driving force for such a reaction is the is high positive heat of formation of the compound that is, extreme instability of the compound.