In this task, you need to answer the given multiple-choice question on the general math. Classify your answers into 'a', 'b', 'c', 'd', and 'e'.

Problem: the population of a city increases by 7 % per year but due to migration it decrease by 1 % per years . what will be the percentage increase in population in 3 years ? 
Options: a ) 9 % , b ) 9.10 % , c ) 27 % , d ) 12 % , e ) none of these
b

Problem: how much percentage 80 is of 480 ? 
Options: a ) 16.5 , b ) 14.33 , c ) 12.5 , d ) 15.8 , e ) 16.66
e

Problem: reduce 368 / 598 to the lowest terms 
Options: a ) 30 / 25 , b ) 28 / 13 , c ) 28 / 29 , d ) 8 / 13 , e ) none of these

d