Task: Question Answering
Input (English): Problem: one copy machine can make 20 copies a minute, and a second copy machine makes 10 copies a minute. if the two copiers work together, how long would it take them to make 900 copies ?
Options: a. 10 minutes, b. 20 minutes, c. 25 minutes, d. 30 minutes, e. 35 minutes
Output (English): d