Answer:
Air inside the guard hairs traps heat close to the body, keeping the reindeer warm even in the frigid, windy temperatures of the tundra. The guard hairs also prevent body heat from escaping and melting the snow if the reindeer lies down, keeping it from getting wet and cold.
 
        
             
        
        
        
Answer:
Movement in narrow zones along plate boundaries causes most earthquakes. Most seismic activity occurs at three types of plate boundaries—divergent, convergent, and transform. As the plates move past each other, they sometimes get caught and pressure builds up.
 
        
             
        
        
        
The mentioned case represents secondary succession.  
Secondary succession is one of the two kinds of ecological succession of plant life. Secondary succession refers to a procedure initiated by an incident, like harvesting, forest fire, hurricane, and others, which minimizes an already settled ecosystem to a lesser population of species.  
Thus, it can be said that the secondary succession takes place in preexisting soil on the other hand primary succession takes place in a place devoid of soil.  
Secondary succession is the ecological succession, which takes place after the initial succession has been disrupted and certain plant and animal species do prevail. It is usually faster in comparison to primary succession.  
 
        
             
        
        
        
B. Subgroups
<span>When constructing a dichotomous key, the first step is to look at the group of objects or organisms and separate them into two groups based on a single distinguishing characteristic.  Then continue to separate each of the groups until each object has its own separate set of characteristics.</span>