Well, this is very easy, first up; what's a fugitive?
A fugitive is a person that has escaped a place/or is in hiding;to avoid arrest/persecution.
So traveling by wagons,railroads,and walking makes sense. Except for one, slave ships, that makes no sense at all. Why would fugitive slaves travel on "slave ships?"
Answer:
They are appointed by the president
Plants need nitrogen to make proteins I believe
