Answer:
1. Answer: Light can travel in a vacuum, and its speed is constant if the source is moving or stationary.  
Light travels at constant speed in vacuum even if the source is moving or stationary. If the source is moving, the apparent frequency/ wavelength changes.
 
        
             
        
        
        
The action or process of transcribing something
        
                    
             
        
        
        
Explanation:
Many birds, such as geese, seasonally fly to warm places when the weather gets cold. They then return when the weather warms. This process is called migration. ... Migration enables many animals to move to places where it is easier for them to survive.