Answer: Option (D) is the correct answer.
Explanation:
Vapor pressure is defined as the pressure exerted by the vapors which are present on the surface of a liquid. 
For example, vapor pressure of water at room temperature is 0.0313 atm.
On the other hand, the temperature at which the vapor pressure of a liquid equals atmospheric pressure is known as boiling point. 
For example, boiling point of water at room temperature is  .
.
Thus, we can conclude that vapor pressure can be described as the pressure exerted by a gas above the surface of its liquid.
 
        
             
        
        
        
Answer:
Natural sources include decomposition, ocean release and respiration. Human sources come from activities like cement production, deforestation as well as the burning of fossil fuels like coal, oil and natural gas.
Explanation:
 
        
             
        
        
        
a pure compound because an element is untouched and is just itself
 
        
                    
             
        
        
        
Answer:
Answer Below! : )
Explanation:
Groundwater is stored in the tiny open spaces between rock and sand, soil, and gravel. How well loosely arranged rock (such as sand and gravel) holds water depends on the size of the rock particles.
Hope this helps! : )