I got an HCI assignment from my lecturer, and I don’t understand it [on hold]

There were two assignments I'd got. The another one I could do it, but not this one( which is shown on this post). I don't know how to give the examples for the description in the assignment by applying those 2 things( the cognitive in a reaction time task and the findings of 7(+2)) given from it. Could anyone give me for some hints or solutions? I've searched the information on the Google to make an apply for the answer, but it still didn't make any sense for me.