Task: Question Answering
Input (English): Problem: a man complete a journey in 10 hours . he travels first half of the journey at the rate of 21 km / hr and second half at the rate of 24 km / hr . find the total journey in km . 
Options: a ) 220 km , b ) 224 km , c ) 230 km , d ) 234 km , e ) 255 km
Output (English): b