Read the following passage and mark the letter A, B, C or D on your answer sheet to indicate the correct answer to each of the questions.
There is one planet that still fascinates and teases scientists mainly because it doesn’t have an atmosphere to obscure observation, yet it is not big enough for sufficiently accurate telescopic observation. The fact that it is also very close to the sun also makes it difficult for astronomers.
However, space telescopes have told us a lot more about Mercury. It is rather similar to Earth’s moon and to Mars. There are mountainous areas dotted with craters and large valleys which are uncratered. The moon’s valleys have fewer cracks and ridges are smoother. Mercury’s valleys are filled with volcanic rocks, similar to on the moon, yet there is no evidence of volcanoes, even extinct ones, on Mercury, as there is on the both Mars and the moon, and of course here on Earth.
So, scientists presume the valleys on Mercury were caused by different things, that is to say not by volcanoes, but by very large meteorites, which also caused the cracks in the terrain and left the ridges rough and uneven. More and better photos of Mercury are at present at best only hypotheses.
Question28. What is the main topic of this passage?
A. Astronomers’ difficulties. C. The Earth’s moon.
B. Observation of planets. D. The planet, Mercury
Question29. Why does Mercury still tease scientists?
A. Because it has an atmosphere which obscures observation.
B. Because it is too close to the sun.
C. Because it is difficult for space probes to get close to.
D. Because it is too small.
Question30. What is true about Mercury but not true about the moon or Mars?
A. The valleys are filled with volcanic rocks. C. There are no volcanoes.
B. The valleys are uncratered. D. They are hilly regions.
Question31. What does the author imply space telescopes can do better than land-based telescopes?
A. Show more of the planet, Mercury. C. Show what caused Mercury’s valleys.
B. Show the meteorites which hit Mercury. D. Show the volcanoes on Mercury.
Question32. What can we infer from the passage that astronomers still need to get more detailed observation of Mercury?
A. More hypotheses C. Larger space telescopes.
B. Better and more space telescopes. D. More ways to prove hypotheses.