D. Listen to a passage and complete the answer to each question (in no more than 3 words). Both the passage and the questions will be read two times. 16. What percentage of the earth's surface is covered with water? About . 17. How can people today travel around the world? By cargo and . 18. What can rivers, lakes and seas provide for human beings? . 19. Where is water ted to water crops in dryer parts of the world? From . 20. What disaster can floods bring to man? Thousands of people die and is done by flood waters.