Question

A graph of coal reserves in the United States versus time slopes downward. This indicates that coal production could have ________.
A. Stayed the same

B. Decreased

C. Increased

D. Fluctuated

I think it’s D

Answer 1

The correct answer is:  [B]:  "decreased" .
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Note:
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        In a graph of "coal reserves in the United States" vs. "time" ; 

→ the "time" is the "independent variable" that belongs on the "x-axis" .

→ The quantity or amount of "coal reserves in the United States" is the "dependent variable" that belongs on the "y-axis" . 

       If the graph "slopes downward" ;  this would indicate a "decrease" in the amount/quantity of "coal reserves" over "time" .  

→  As the value of "x" increases — "time" increases — and; as "x" increases, the value of "y" {the amount/quantity of "coal reserves"} decreases.  

→ This would be represented by a "downward sloping" graph;  

→  and, among the answer choices given, could indicate that coal production:
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                     →  "decreased" ;    
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→  which is:  Answer choice:  [B]:  "decreased" .
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Answer 2

Answer:

b decreased

Explanation: