Task: Question Answering
Input (English): Problem: a man takes twice as long to row a distance against the stream as to row the same distance in favour of the stream. the ratio of the speed of the boat ( in still water ) and the stream is
Options: a. 1: 2, b. 1: 3, c. 2: 1, d. 3: 1, e. none
Output (English): d