Question 198651
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*[tex \LARGE \ \ \ \ \ \ \ \ \ \ D_c = \left(\frac{A_c}{A_c+12}\right)D_a]


Solve for *[tex \Large D_a]:


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ D_a = \left(\frac{A_c + 12}{A_c}\right)D_c]


Substitute values:


*[tex \LARGE \ \ \ \ \ \ \ \ \ \ D_a = \left(\frac{12 + 12}{12}\right)15]


Do the arithmetic.  You can do that yourself.


John
*[tex \LARGE e^{i\pi} + 1 = 0]
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