Answer:
C) electromagnetic waves must have a medium in which to travel, but sound waves can travel anywhere.
Explanation:
Electromagnetic waves do not require a medium to travel. they can travel through vacuum also. for example:- light wave is an electromagnetic wave and it can travel through vacuum also.
On the other hand, sound wave require a medium to travel. sound waves can not travel through vacuum.
I HOPE IT WILL HELP YOU?:-) 
 
        
             
        
        
        
Answer:
The circulatory system is made up of blood vessels that carry blood away from and towards the heart. Arteries carry blood away from the heart and veins carry blood back to the heart. The circulatory system carries oxygen, nutrients, and hormones to cells, and removes waste products, like carbon dioxide.
Explanation:
 
        
                    
             
        
        
        
Answer:
Urey and miller cooked a "primordial soup" with Hadean gases, water and electricity to make <u>glucose</u>, <u>acetic acid</u>, <u>amino acids</u> and <u>lipids</u>.
Explanation:
In the Miller-Urey experiment, the aim was to reproduce the conditions of the earth before the existence of life, with the objective of demonstrating the formation of organic matter from inorganic molecules.
The scientists took water and gases present in the Hadean eon —previous to the existence of life— such as methane, carbon dioxide, hydrogen, nitrogen and even ammonia, the primordial soup. This mixture was subjected to electrical discharges, inside closed containers.
The results were some organic molecules, including glucose, acetic acid, amino acids and fatty acids. In these results the presence of macromolecules, such as proteins or nucleic acids, is not appreciated, however it was a significant contribution to the knowledge of the origin of life on earth.
 
        
             
        
        
        
There are many ways you can reduce power consumption.
You can take shorter showers, turn of your lights before leaving the house, using less appliances. If you need more, comment below. Hope this helps..
        
                    
             
        
        
        
They help work together because when the heart pmps blood through the body and the cells flow through the blood non stop its like a barrier of protection