9. I can travel upriver against the current. I am fast, efficient, and fun. I can carry lots of people, goods, and raw materials up and down rivers easily at 10 miles per hour. I helped the cities that live along the river grow into larger cities. What am I? __________________
10. I reduced the time it takes to travel over land. Unlike many other forms of transportation, I can be used year-round and carry heavy loads. What am I? _______________________
11. The use of steam power really did revolutionize transportation. However, in the beginning, steam power in boats and trains had a few disadvantages. Name two of them. ________________________________________________________________________ ________________________________________________________________________