Task: Question Answering
Input (English): Problem: chlorination is used in industry for the purification of water ; 1 gm solution of chlorine will remove half of the germs in 1 liter of water . if water containing less than 0.09 % of germs is considered clean , what is the minimum amount of chlorine required to purify 150 liter of water containing 0.3 liter of harmful substances ? 
Options: a ) 1 , b ) 2 , c ) 3 , d ) 4 , e ) 5
Output (English): b