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: in one hour , a boat goes 8 km along the stream and 2 km against the stream . the sped of the boat in still water ( in km / hr ) is : 
Options: a ) 3 , b ) 5 , c ) 8 , d ) 9 , e ) 10
b

Problem: if 15 % of 40 is greater than 25 % of a number by 2 , the number is 
Options: a ) 14 , b ) 16 , c ) 18 , d ) 20 , e ) 22
b

Problem: a sum of money at simple interest amounts to 815 in 3 years and to 854 in 4 years . the sum is : 
Options: a ) 698 , b ) 387 , c ) 373 , d ) 593 , e ) 372

a