Groundwater supplies drinking water for 51% of the total U.S. population and 99% of the rural population. Groundwater helps grow our food 64% of groundwater is used for irrigation to grow crops. Groundwater is an important component in many industrial processes.
 
        
             
        
        
        
It is called a herd 
Im just writing this for the character limit
        
             
        
        
        
<span>Water heats up, changes to water vapor and evaporates, rises into the sky. It cools, condenses, turns back into liquid water forming clouds. Then it falls back to earth as precipitation and runs down hills or mountains during runoff and returns to lakes and oceans.
I think i`m not sure :)</span>
        
                    
             
        
        
        
Answer:
Nitrogen is a crucially important component for all life. It is an important part of many cells and processes such as amino acids, proteins and even our DNA. It is also needed to make chlorophyll in plants, which is used in photosynthesis to make their food.
 
        
             
        
        
        
Answer:
- It has a vital role. It is the only way out of the optic nerve. By this hole optic nerve exits from the eye and goes towards the brain.
- It can be proved by a simple experiment. A paper sheet is taken. Then a cross and a circle are drawn side by side on that paper. Then we will focus on the cross. Then by closing one eye and by bringing the paper slowly towards our face, the circle will be disappeared at a certain point.        
Explanation:  
The blind spot is a region on the retina where ganglion cells connect with the optic nerve, and the optic nerve and blood vessels leave the eyeball. There are no receptors in this area so nothing can be translated into vision. That's why the blind spot is unable to see things.