Task: Question Answering
Input (English): Problem: the distance between 2 cities a and b is 1000 km . a train starts from a at 11 a . m . and travels towards b at 100 km / hr . another starts from b at 12 p . m . and travels towards a at 150 km / hr . at what time do they meet ? 
Options: a ) 11 am . , b ) 12 p . m . , c ) 3 pm . , d ) 4 p . m . , e ) 1 p . m .
Output (English): d