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: find the least number of 5 digits which is exactly divisible by 12 , 15 and 18 ? 
Options: a ) 1080 , b ) 10080 , c ) 10025 , d ) 11080 , e ) 12080
b

Problem: ifaequals the sum of the even integers from 2 to 20 , inclusive , andbequals the sum of the odd integers from 1 to 19 , inclusive , what is the value of b - a ? 
Options: a ) - 10 , b ) 10 , c ) - 19 , d ) 20 , e ) 21
a

Problem: the product z of two prime numbers is between 20 and 56 . if one of the prime numbers is greater than 2 but less than 6 and the other is greater than 14 but less than 30 then what is z ? 
Options: a ) 26 , b ) 35 , c ) 39 , d ) 51 , e ) 55

d