<span>the high expense; electron microscopes are costly</span>
        
             
        
        
        
Answer:
 #IN GIRLS
* adolsence 
* menstruation 
#IN BOYS
* penis strts turning big
*beard starts coming of face 
 
        
                    
             
        
        
        
The answer to this question would be :4.) SpeciesIn taxonomy, the organism will be divided into different groups based on a specific character from that organism. It could be an organ 
The sequence from top to bottom would be:
<span>life
<span>domain
</span><span>kingdom
</span><span>phylum 
</span><span>class
</span><span>order
</span><span>family
</span><span>genus
</span><span>species
The lowest subgroup is called species</span></span>
        
                    
             
        
        
        
Answer:
Differences in their boiling points 
Explanation:
When crude oil is distilled and separated into categories, the categories are characterized by the differences in their boiling points. 
At different boiling points, each of the fraction will separate out. 
- Crude oil is made up of different fractions of hydrocarbons. 
- As the chain length of the hydrocarbon increases, the volatility reduces and boiling point increases. 
- Components with short carbon lengths rises out from the column first and are cooled and extracted. 
- The categories are thereby, classified based on differences in their boiling points.