Question

Write the name of the longest river of the United States of America, as shown on the outline map of the World.

Hint:

Longest river of the United States of America

Answer 1

Step 1: Recall the two rivers that meet near St. Louis.
The Missouri joins the Mississippi near St. Louis; measured from its own most distant source, the Missouri is slightly longer than the Mississippi alone.

Final Answer:
The Missouri River is the one to mark as the USA's longest river.$\boxed{\text{Missouri River}}$