Answer: Arctic Ocean 
Explanation:
Because the Arctic Ocean is colder it is more dense
 
        
             
        
        
        
Answer:
Surface temperature and lower air pressure.
Explanation:
Surface temperature and lower air pressure are the types of data would a meteorologist need to collect in order to demonstrate the presence of a cyclone in a specific region. For the formation of cyclone, warm and moist air is required so surface temperature and lower air pressure are the data that gives information that the cyclone is present in a particular area or not.
 
        
             
        
        
        
The term would be leukocytosis and this usually indicates that there is presence of an infection.