Ordering Information in a Paragraph

Read the paragraphs and number the topics in the order they are presented. Write na for topics that are not included in the paragraph.




          Earth is the third planet from the sun in our solar system. Earth is not the largest planet in the solar system. It is much smaller than Jupiter, Saturn, Uranus, or Neptune. However, it is much larger than Mercury, Venus, or Pluto. Like the other planets, Earth travels in an orbit around the sun. It takes about 365 Earth days to complete one revolution. A day is the amount of time that it takes the Earth to rotate once. An Earth day is 24 hours long.
          As far as we know, Earth is the only planet in our solar system that is inhabited. Some scientists believe that there may have been primitive life on Mars, but this has not been proven. Earth is the only planet where human beings could live because humans need oxygen, and earth's atmosphere is composed of nitrogen and oxygen. In addition to the absence of oxygen, the other planets would present many other problems for humans. For example, Venus has 220 m.p.h. winds. Mercury is much too hot, and the more distant planets, such as Saturn, Neptune, Uranus, and Pluto, are much too cold.

1		discovery
2		length of day, year
3		position
4		composition of atmosphere
5		moons
6		comparison of earth and other planets as a place for humans to live
7		relative size