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: a rainstorm increased the amount of water stored in state j reservoirs from 124 billion gallons to 140 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 ) 51 , b ) 48 , c ) 55 , d ) 63 , e ) 65

A: a
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Q: Problem: if 25 % of x is 30 less than 20 % of 1000 , then x is ? 
Options: a ) 188 , b ) 216 , c ) 156 , d ) 680 , e ) 121

A: d
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Q: Problem: simplify : 896 x 896 - 204 x 204 
Options: a ) 761200 , b ) 761400 , c ) 761800 , d ) 761500 , e ) none of them

A:
a
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