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: a trader bought a car at 20 % discount on its original price . he sold it at a 55 % increase on the price he bought it . what percent of profit did he make on the original price ? 
Options: a ) 17 % , b ) 24 % , c ) 12 % , d ) 82 % , e ) 16 %
b

Problem: in an office , 20 percent of the workers have at least 5 years of service , and a total of 16 workers have at least 10 years of service . if 90 percent of the workers have fewer than 10 years of service , how many of the workers have at least 5 but fewer than 10 years of service ? 
Options: a ) 32 , b ) 64 , c ) 50 , d ) 144 , e ) 160
a

Problem: how many liters of a 40 % iodine solution need to be mixed with 35 liters of a 20 % iodine solution to create a 33 % iodine solution ? 
Options: a ) 35 , b ) 49 , c ) 100 , d ) 105 , e ) 122

e