1-C. Both Hannibal and St. Louis are located on the Mississippi River.Both Hannibal and St. Louis are located on the Mississippi River.
ハンニバルとセントルイスの両方が、ミシシッピ川に位置しています。
2-C. It's just a couple of hours' bus ride from St. Louis along the Mississippi River.It's just a couple of hours' bus ride from St. Louis along the Mississippi River.