Read the following SAT test question and then click on a button to select your answer. 

The functionis graphedin theabove. If the functionis defined by, for how many values of  between  and  does  equal ?

(A) None 
(B) One
(C) Two
(D) Three
(E) More than three

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The correct answer is C

Explanation

The graph of the function  is the same as the graph of the function  translated up  units. The function  intersects the  three times, but if the graph is shifted up  units, then the graph will intersect the  only twice. Therefore,  is equal to  for exactly two values of  between  and .