Task: Question Answering
Input (English): Problem: among the two clocks , clock a gains 20 seconds per minute . if clock a and b are set at 2 0 ' clock , when clock a is at 7 : 20 , what does clock b show ? 
Options: a ) 5 : 30 , b ) 6 : 00 , c ) 5 : 45 , d ) 6 : 20 , e ) 3 : 30
Output (English): b