It’s pretty obvious. Given that there are open pipes only to 5 and 9, it would have to be one of those two. Furthermore, there is a large reservoir near #5 that would fill first, and the pipe leading to #9 is lower than the pipe leading to #5, I think cup 9 would be overflowing without any coffee ever making it to cup 5.
Best explanation yet.
9 is blocked too.
Bah, I didn’t notice that the pipe to 9 is also blocked. So 5 will fill up, but only after that large reservoir is filled. I’m assuming airflow is unimpeded as the coffee pours in—although the diameter of the pipes could prevent air from escaping, in which case the coffee will fill the first reservoir and proceed to run all over the floor.
You need to be a little more obvious ma’am.
#9 is blocked
9 is blocked