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: on selling 17 balls at rs . 720 , there is a loss equal to the cost price of 5 balls . the cost price of a ball is 
Options: a ) 20 , b ) 30 , c ) 40 , d ) 50 , e ) 60

A: e
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Q: Problem: in the manufacture of a certain product , 5 percent of the units produced are defective and 4 percent of the defective units are shipped for sale . what percent of the units produced are defective units that are shipped for sale ? 
Options: a ) 0.125 % , b ) 0.2 % , c ) 0.8 % , d ) 1.25 % , e ) 2.0 %

A: b
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Q: Problem: what is the rate percent when the simple interest on rs . 810 amount to rs . 155 in 4 years ? 
Options: a ) 4.78 , b ) 4.68 , c ) 4.58 , d ) 4.48 , e ) 4.38

A:
a
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