One group of reptiles, characterized by the fossil Archaeopteryx, led to the evolution of birds. The correct answer is birds
 
        
                    
             
        
        
        
the two main skeletal systems to support the tissue of the body is bone and cartilage 
hopefully this will help 
 
        
             
        
        
        
It is a form of natural selection called sexual selection. 
        
             
        
        
        
Answer is Tropical. 
The climate of a region is determined temperature and precipitation. Actually the climate of Pennsylvania is humid Subtropical climate. It is characterized by high temperatures and evenly distributed precipitation throughout the year. The average temperature for the year is 55.9°F (13.3°C). The warmest month, on average is July and coolest month is January. The average amount of precipitation for the year is 41.5" (1054.1 mm). The month with the most precipitation on average is also July.
 
        
                    
             
        
        
        
Body composition:<span>is the percentage of person's total body weight that is made up of adipose (fat) tissue as opposed to lean body tissue is known as their body composition. Disease risk is closely related to body composition.
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