The rate of cratering in the lunar highlands shows us that:
A) they must be younger than the older, darker mare.
B) they range from 4.6-4.4 billion years old, on average.
C) the largest impacts are the youngest, such as Copernicus and Tycho.
D) the oldest rocks are at least as old as the mare, but some craters are much younger.
E) most of the asteroids must have hit the Moon, not the Earth.
B
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An observer on a planet sees a spaceship approaching at 0.5c. A beam of light projected by the ship would be measured by this observer to travel at:
A) 0.25c. B) 0.5c. C) c. D) 1.5c. E) 2.5c.
An equilibrium between solute dissolving and solute crystallizing is characteristic of which of the following solution types?
a. Saturated b. Unsaturated c. Supersaturated d. Concentrated
Approximately how many times does an average human heart beat in a lifetime?
A) 3 × 1011 B) 3 × 1010 C) 3 × 109 D) 3 × 108 E) 4 × 107
Which of the following statements about an ellipse is not true?
A) The semimajor axis of an ellipse is half the length of the longest line that you can draw across an ellipse. B) An ellipse with a large eccentricity looks much more elongated (stretched out) than an ellipse with a small eccentricity. C) A circle is considered to be a special type of ellipse. D) The focus of an ellipse is always located precisely at the center of the ellipse.