Answer:
Option D 
Fish
Explanation:
The characteristics of index fossil is distinctive, widespread, abundant, and limited in geologic time. Ammonites fit these demands well and are the best-known fossils that have been widely used for this.
Thus, The answer is Fish
 
 
        
                    
             
        
        
        
Answer:
It would seem that the answer in the question is correct
Explanation:
 falls in the form of ice or snow is already unusable because of acid rain evaporates back into the atmosphere is taken up by plants or other organisms either runs off to form rivers or filters down into underground aquifers 
Not sure what the question was here 
 
        
             
        
        
        
5x-2=8                                                                                                                       add 2 to both sides                                                                                            5x=10                                                                                                                        divide both sides by 5                                                                                   x=2
        
                    
             
        
        
        
Answer: 
human factors: 
Access to a freshwater supply is affected by the following factors: Climate – low levels of rainfall and high temperatures lead to water deficits . When rainfall is low, there is less water available. When temperatures are high, water evaporates and so there is less available to use.
environmental factors:
 Sedimentation.
Runoff.
Erosion.
Dissolved oxygen.
pH.
Temperature.
Decayed organic materials.
Pesticides.
Explanation: 
no explanation. already explained in the answer
 
        
             
        
        
        
Sunday, July 20, marked 45 years since the United States put the first two astronauts safely on the moon. The cost for the Mercury, Gemini and Apollo programs was more than $25 billion at the time more like $110 billion in today’s world. The ensuing U.S. space efforts have cost an additional $196 billion for the shuttle and $50 billion for the space station. NASA’s total inflation-adjusted costs have been more than $900 billion since its creation in 1958 through 2014 (more than $16 billion per year). Looking back, have we gotten our money’s worth from the investment?
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