Task: Question Answering
Input (English): Problem: in a flight of 600 km , an aircraft was slowed down due to bad weather . its average speed for the trip was reduced by 200 km / hr and the time of flight increased by 30 minutes . the duration of the flight is ? 
Options: a ) 1 hr , b ) 2 hr , c ) 6 hr , d ) 8 hr , e ) 7 hr
Output (English): a