Question 1142872
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We can assume that the boy started at the origin of the coordinate plane, at the point (x,y) = (0,0).


Then his consecutive starting-turning-ending points on the coordinate plane are


    (0,0)  ----> (0,-4) ---->  (6,-4) ---->  (6,0).


The distance between the starting and ending points is 6 miles.    <U>ANSWER</U>
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