What are the Great Lakes often called?
5. Which is the westernmost lake and the largest? Which is the smallest? 6. Into what river does Lake Superior drain at its southeastern corner? 7. Why does Lake Huron act as a bridge within the Great Lakes system? 8. Why do scientists consider Lake Michigan and Lake Huron twins? 9. Into what river does Lake Erie empty at its eastern end? In the next thirty-five miles, how many feet does it drop and over what falls? 10. What has been built to allow ships to bypass the rapids of the St. Marys River? 11. Why does the article refer to the St. Lawrence Seaway as a stairway? 12. What sister cities have ports that are among the busiest in the United States? 13. What cargo do ships haul among the various cities on the lake? 14. Name three things provided by the Great Lakes. 15. At the time of this article, how much money did recreational fishing add to the region’s economy? 16. In what ways have humans damaged the lakes? 17. What do scientists believe we can do to maintain the Great Lakes as
