1700´s is the right answer
ANSWER
Two different species of mice migrated to the river from different directions.
EXPLANATION
Solved scientifically in my head.
Answer:
My house is bigger than yours.
Your grade is worse than mine.
The Pacific Ocean is deeper than the Arctic Ocean.
You are more polite than Joey.
My brother is taller than I am, but he is older too.
Answer: Oona is planning to ambush the Russians.
In this excerpt, we see that Oona is instructing Negore as to how to lead the Russians. Oona states that Negore should show them the way, to where they wait in a passage up the rocks. The fact that they are hidden, and that they are waiting for the Russians to pass, along with their negative attitude towards them, implies that they are planning an ambush for the Russians.