Hybrid inviability is when a hybrid animal is biologically unable to grow up to be a healthy mature adult. This condition results in isolation from hybrids and pure breeds.
Hybrid infertility is a conditio experienced by hybrid animals when they cannot reproduce. This prevents the spreading of the hyrbid species into uncontrollable populations.
        
             
        
        
        
Answer: Option B
Explanation:
In a typical energy pyramid the amount of energy that is being transferred is only 10% rest of the energy is lost in the form of heat.
The energy from the sun is converted in the form of chemical energy which is stored in the producers.
10 per cent of this energy is transferred to the next trophic level and rest of the energy is lost in the form of heat. This goes on, there is only a transfer of 10 % energy from the successive levels.
So, if the producers have 200 Kcal/m2/year energy the the primary consumers will have 10% of this energy which is equivalent to 20 Kcal/m2/year and then the secondary consumers will have 10 % of 20 Kcal/m2/year which is equivalent to 2 Kcal/m2/year.
 
        
                    
             
        
        
        
Answer: adenine, thymine, guanine and cytosine 
Explanation: Adenine always binds with thymine, and cytosine always binds with guanine.