Task: Question Answering
Input (English): Problem: a man engaged a servant on the condition that he would pay him rs . 800 and a uniform after one year service . he served only for 9 months and received uniform and rs . 400 , find the price of the uniform ? 
Options: a ) s . 800 , b ) s . 85 , c ) s . 90 , d ) s . 100 , e ) s . 120
Output (English): a