Question 1144076
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If the temperature at 9:00 Pm was 12 degrees Fahrenheit and 6 hours {{{highlight(later)}}} the temperature 
dropped to 6 degrees Fahrenheit below zero, what was the rate of change in temperature per hour? 
A)2
B)3
C)4
D)5
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            Pay attention on how I edited your post to make sense.



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. . . Then the rate of change was  {{{((-6) - 12)/6}}} = {{{(-18)/6}}} = -3 degrees of Fahrenheit per hour,


<U>which  // (!) ATTENTION (!) //  is not in your option list</U>.



To get the answer, you should subtract the present value of the temperature from its future value and to divide 

this difference by the duration of the time period.
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