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 reduction of 23 % in the price of salt enables a lady to obtain 10 kgs more for rs . 100 , find the original price per kg ? 
Options: a ) s . 2.99 , b ) s . 2.4 , c ) s . 2.5 , d ) s . 2.2 , e ) s . 2.1

A: a
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Q: Problem: a trader sells 40 metres of cloth for rs . 8200 at a profit of rs . 35 per metre of cloth . how much profit will the trder earn on 40 metres of cloth ? 
Options: a ) rs . 950 , b ) rs . 1500 , c ) rs . 1000 , d ) rs . 1400 , e ) none of these

A: d
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Q: Problem: if it is assumed that 60 percent of those who receive a questionnaire by mail will respond and 210 responses are needed , what is the minimum number of questionnaires that should be mailed ? 
Options: a ) 290 , b ) 320 , c ) 350 , d ) 380 , e ) 410

A:
c
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