Question

C. After the explorers reached the sources of

the Missouri River, they crossed mountains
and found another river flowing west. What
was the name of the river?

Answer 1

The river that the explorers found flowing west after crossing the mountains was the Columbia River.

Step-by-step explanation:

The river that the explorers found flowing west after crossing the mountains from the sources of the Missouri River is the Columbia River. The Columbia River is the largest river in the Pacific Northwest region of North America and it flows through Washington and Oregon, eventually emptying into the Pacific Ocean.

Learn more about Exploration of rivers in North America