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'.

Problem: x and y started a business by investing rs . 36000 and rs . 42000 respectively after 4 months z joined in the business with an investment of rs . 48000 , then find share of z in the profit of rs . 13860 ? 
Options: a ) 4032 , b ) 4000 , c ) 3250 , d ) 3825 , e ) 3985
a

Problem: a man can row his boat with the stream at 19 km / h and against the stream in 11 km / h . the man ' s rate is ? 
Options: a ) 4 kmph , b ) 2 kmph , c ) 7 kmph , d ) 8 kmph , e ) 3 kmph
a

Problem: if x is invested in a bank at a rate of simple interest of y % p . a . for two years , then the interest earned is 300 . if x is invested at y % p . a . , for two years when the interest is compounded annually , the interest is 307.50 . what is the value of x ? 
Options: a ) 8000 , b ) 6000 , c ) 5000 , d ) 4000 , e ) 3000

e