I want to know the answer to the following question:
In what areas were Han ships able to be sailed in part due to the stern rudder?
All the background I'm provided with is that "Moreover, Han ships were the first in the world to be steered using a rudder at the stern, in contrast to the simpler steering oar used for riverine transport, allowing them to sail on the high seas.". Is that enough to answer the question?
Answer: yes