1. The earth is the only planet with a large number of oxygen in its atmosphere.
A B C D
2. Venus approaches the Earth more closely than any other planet is.
A B C D
3. Robert Frost was not well known as a poet until he reached the forties.
A B C D
4. The amounts of oxygen and nitrogen in the air almost always remain stable, but the amount of water vapor vary considerably.
A B C D