The X symbol looks too much like the multiplication symbol, it also makes using it as a variable more confusing.
        
                    
             
        
        
        
Answer:
The main function of the alveoli is storage of air for a shorter period which permits absorption of oxygen into the blood. The gaseous exchange of oxygen and carbon dioxide typically takes place in the alveoli. The main function of the bronchiole is to allow the passage of air freely into the lungs
 
        
                    
             
        
        
        
A lion, coyote, and others like hawks and eagles
        
             
        
        
        
One way is to see if it responds to stimulants or if it reproduces
        
             
        
        
        
<u>Answer</u>: Hybridization.
Hybridization is the process through which two species can mate with each other and produce fertile offspring thus creating a new species. 
This is not happening with the two palm species on the island. This may be due to prezygotic barriers that prevent these two species from mating and producing a zygote (fertilized egg cell). In essence these barriers prevent any gene flow between the two species.