Task: Question Answering
Input (English): Problem: without stoppages , a train travels certain distance with an average speed of 250 km / h , and with stoppages , it covers the same distance with an average speed of 125 km / h . how many minutes per hour the train stops ? 
Options: a ) 25 , b ) 30 , c ) 35 , d ) 40 , e ) 45
Output (English): b