TASK DEFINITION: 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'.
PROBLEM: Problem: the tax on a commodity is diminished by 30 % but its consumption is increased by 15 % . find the decrease percent in the revenue derived from it ? 
Options: a ) 20 % , b ) 18 % , c ) 15 % , d ) 12 % , e ) 14 %

SOLUTION: a

PROBLEM: Problem: if 2 ^ ( 2 w ) = 8 ^ ( w − 3 ) , what is the value of w ? 
Options: a ) 3 , b ) 6 , c ) 9 , d ) 12 , e ) 15

SOLUTION: c

PROBLEM: Problem: a rainstorm increased the amount of water stored in state j reservoirs from 130 billion gallons to 160 billion gallons . if the storm increased the amount of water in the reservoirs to 80 percent of total capacity , approximately how many billion gallons of water were the reservoirs short of total capacity prior to the storm ? 
Options: a ) 75 , b ) 70 , c ) 65 , d ) 85 , e ) 90

SOLUTION:
b