In this task, you need to answer the given multiple-choice question on the general math. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Q: Problem: for what values of k will the pair of equations 4 ( 3 x + 4 y ) = 48 and kx + 12 y = 30 does not have a unique solution ? 
Options: a ) 12 , b ) 9 , c ) 3 , d ) 7.5 , e ) 2.5

A: b
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Q: Problem: the tax on a commodity is diminished by 32 % but its consumption is increased by 12 % . find the decrease percent in the revenue derived from it ? 
Options: a ) 20 % , b ) 18 % , c ) 15 % , d ) 12 % , e ) 24 %

A: e
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Q: Problem: at 1 : 00 pm , there were 10.0 grams of bacteria . the bacteria increased to x grams at 4 : 00 pm , and 25.6 grams at 7 : 00 pm . if the amount of bacteria present increased by the same fraction during each of the 3 - hour periods , how many grams of bacteria were present at 4 : 00 pm ? 
Options: a ) 15.1 , b ) 15.4 , c ) 15.7 , d ) 16.0 , e ) 16.3

A:
d
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