A predator takes 20 minutes to process a
prey item. How many prey can it eat if
prey densities are sufficient to allow 1 encounter per hour? what about 2 encounters/hour? 5 encounters/ hour?

I am still a little confused at the question. I think the "encounter" throws me off. I understand the first question (3 preys because 60mins/20min= 3 preys. However, for number 2, it is said what if the predator had 2 encounters per hour? I'm confused because aren't they still asking about the number of preys at this point? I notice that you put hours.