Final answer:
Canoeing upstream near the shore and downstream near the middle is advised due to the speed of the current.
Step-by-step explanation:
When paddling a canoe upstream, it is wisest to travel as near to the shore as possible. This is because the current is slower near the shore, making it easier to paddle against the flow of the river. On the other hand, when canoeing downstream, it may be best to stay near the middle. This is because the current is faster in the middle of the river, allowing the canoe to travel faster with the flow of the river.