Answer:
Active heating captures sunlight, either as heat or electricity, to augment heating systems, while passive heating captures heat from the sun as it comes into your home through windows, roofs and walls to heat objects in your home (hope that helped?)
Explanation:
 
        
             
        
        
        
Cellular<span> differentiation is the process by which a less specialized </span>cell<span> becomes a more specialized </span>cell<span> type. Differentiation occurs numerous times during the development of a </span>multicellular organism<span> as the </span>organism<span> changes from a simple zygote to a complex system of tissues and </span>cell<span> types.
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I'm not 100% sure, but I'd say the availability of vaccines and medicine.
 
        
             
        
        
        
<span>If a baby is born with two X chromosomes, it must be female. Males have XY chromosomes, females have XX chromosomes, due to how the chromosomes are naturally passed from parents to a child.</span>