Answer:
36 pounds
Explanation:
First of all, since they aren't asking about nuts, we can ignore the information regarding them; it's irrelevant.
In 6 hours, Susan will pick 4 * 6 which is 24 pounds of coffee.
In 6 hours, Tom will pick 2 * 6 which is 12 pounds of coffee.
So, altogether, in 6 hours they can pick a maximum of 36 pounds of coffee (they don't gather nuts).
Hope this helps :)