Task: Question Answering
Input (English): Problem: the cross - section of a water channel is a trapezium in shape . if the channel is 12 meters wide at the top and 6 meters wide at the bottom and the area of cross - section is 630 square meters , what is the depth of the channel ( in meters ) ? 
Options: a ) 50 , b ) 60 , c ) 70 , d ) 80 , e ) 90
Output (English): c