1. Iceland was once B) magma that rose from the Mid-Atlantic Ridge.
2. The spacecraft that landed on Mars found A) signs of life.
3. A planet with two satellites is B) Mars.
4. The dinosaurs disappeared at the end of C) the Mesozoic era
5. The maria of the moon are covered with B) hard, smooth rock.
6. Iridium is an element relatively B) rare on earth but abundant in meteorites.
7. An eclipse of the sun can occur A) only when the moon passes directly between the earth and the sun.
8. The planet with the shortest year is A) Mercury
9. Meteor showers occur A) at the same times each year.
10. At one time during the Paleozoic era B) two-thirds of North America was covered by water.
11. The planets are visible because C) they reflect sunlight.
12. At full moon, the moon is B) on the opposite side of the earth from the sun.
13. Relative to the thickness of the earth’s crust under the oceans, under the continents the crust is A) thinner.
14. Gondwana did not contain A) North America.
15. Polar ice caps are found on C) Mars.
16. When visibility is good and there are no meteor showers, it is possible to see about 5 to 10 meteors per D) week.
17. The most recent division of geologic time is D) the Cenozoic era.
18. The surface of Mars does not contain A) active volcanoes.
19. In the course of 100 years, a lithosphere plate will typically have moved B) 3 m.
20. Which one of the following is not a fossil? D) ancient raindrop impressions preserved in shale