Final answer:
When paddling a canoe upstream, it is best to stay near the shore as the current is weaker there. When paddling downstream, it is best to stay near the middle to avoid turbulent areas near the shore caused by the current.
Step-by-step explanation:
When paddling a canoe upstream, it is wisest to stay near the shore, while when canoeing downstream, it is best to stay near the middle. This is because the current behaves differently in these two scenarios.
When paddling upstream, the current is stronger near the middle of the river, while it is weaker near the shore. By staying near the shore, paddlers can take advantage of the weaker current and reduce the amount of effort required to paddle against it.
On the other hand, when paddling downstream, the current is generally stronger near the shore due to friction with the riverbed. By staying near the middle, paddlers can avoid getting caught in eddies and other turbulent areas created by the interaction of the current with obstacles along the shore.