Task: Question Answering
Input (English): Problem: a dealer offers a cash discount of 10 % and still makes a profit of 20 % when he further allows 45 articles to be sold at the cost price of 40 articles to a particular sticky bargainer . how much percent above the cost price were his articles listed ? 
Options: a ) 40 % , b ) 50 % , c ) 55 % , d ) 80 % , e ) 90 %
Output (English): b