In this task, you need to answer the given multiple-choice question on the gain. Gain is the value by which to multiply the input. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Q: Problem: a glass was filled with 40 ounces of water , and 0.01 ounce of the water evaporated each day during a 20 - day period . what percent of the original amount of water evaporated during this period ? 
Options: a ) 0.005 % , b ) 0.02 % , c ) 0.5 % , d ) 5 % , e ) 20 %

A: c
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Q: Problem: a watch was sold at a loss of 21 % . if it was sold for rs . 140 more , there would have been a gain of 4 % . what is the cost price ? 
Options: a ) 560 , b ) 882 , c ) 799 , d ) 778 , e ) 901

A: a
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Q: Problem: a shopkeeper fixes the marked price of an item 35 % above its cost price . the percentage of discount allowed to gain 8 % is 
Options: a ) 20 % , b ) 27 % , c ) 31 % , d ) 43 % , e ) none

A:
a
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