B.)10 inches
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you need to plug in 10
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thats if you don't know what to do
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the easy way
so the ODE is indeed exact and there is a solution of the form 
. We have
With 
, we have
so
12 black and white, 18 color in one row
6 black and white, 9 color in two rows
4 black and white, 6 color in three rows
2 black and white, 3 color in six rows
Georgia is correct because there is four numbers after the decimal
-0.8b+4.1c-(-3.2b)-0.1c
-(-3.2b)= 3.2b
4.1c-0.1c=4c
-0.8b+4c+3.2b
-0.8b+3.2b=2.4b
4c+2.4b
