Answer: Ecosystem
Explanation: An ecosystem consists of all the biotic and abiotic factors in an area and their interactions. A niche refers to the role of a species in its ecosystem. A habitat is the physical environment in which a species lives and to which it is adapted.
 
        
                    
             
        
        
        
Answer:
Contact the Centers for Disease Control and Prevention (CDC).
Explanation:
 
        
             
        
        
        
Answer:
Neutral
Explanation:
The charge of an oxygen atom is neutral.
 
        
             
        
        
        
Laurentia<span> (</span>North American Craton<span>) is a large continental </span>craton<span> that forms the ancient geological core of the </span>North American<span> continent. Many times in its past, Laurentia has been a separate </span>continent<span> as it is now in the form of North America, although originally it also included the cratonic areas of </span>Greenland<span> and also the northwestern part of </span>Scotland, known as theHebridean Terrane<span>. During other times in its past, Laurentia has been part of larger continents and </span>supercontinents<span> and itself consists of many smaller </span>terranes<span> assembled on a network of Early </span>Proterozoic orogenic<span> belts. Small </span>microcontinents<span> and oceanic islands collided with and sutured onto the ever-growing Laurentia, and together formed the stable </span>Precambriancraton seen today.