1. The author refers to the ocean bottom as a "frontier" in line 2 because it
(A) is not a popular area for scientific research
(B) contains a wide variety of life forms
(C) attracts courageous explorers
(D) is an unknown territory

47. Most travelers retain in their memory different f ine impressions of the place they have visited. Some are impressed by the hospitality of its people. (A) Some are struck by the scenic beauty. (B) Some are not attracted to the local scenery and afraid of trying new food. (C) Others fall in love with specif ic local cultures or with the food. (D) All these feelings can be experienced in Taiwan.

48. Geologists are working hard to better understand why volcanoes erupt, so they can warn people in advance. (A) Earthquakes often precede an eruption. (B) In addition, many eruptions are accompanied by heavy rains. (C) However, because the quakes may come months before the blast, or only hours before, they cannot be used for precise forecasts. (D) This is why it is hard for researchers to predict when a volcano like Mt. St. Lorenzo will erupt again in the future. 

49. (1) The water can be warm or cold. (2) This is a little diff icult to do but it usually works. (3) My father has an interesting method of stopping hiccoughs. (4) Next, he takes the glass in one hand and pinches his nose with the other hand. (5) First, he takes a glass and f ills it with water. (6) Then he bends forward at his waist and drinks the water in very small sips. (A) 35146 2 (B) 32 5 4 1 6 (C) 354612 (D) 321564

50. (1) How do we know great photos when we see them? (2) Most importantly, they put smiles on our faces instantly. (3) While digital cameras make the act of taking lots of pictures simpler, quantity does not necessarily guarantee quality. (4) They’re the pictures that capture our memories and freeze special moments in time. (5) Getting those perfect shots, however, is not always easy. (6) We share them with family and friends and want to be sure they last forever. (A) 12435 6 (B) 14 6 5 3 2 (C) 126435 (D) 146253

2. The word "inaccessible" in line 3 is closest in meaning to (A) unrecognizable (B) unreachable (C) unusable (D) unsafe

3. The author mentions outer space in line 7 because (A) the Earth's climate millions of years ago was similar to conditions in outer space (B) it is similar to the ocean floor in being alien to the human environment (C) rock formations in outer space are similar to those found on the ocean floor (D) techniques used by scientists to explore outer space were similar to those used in ocean exploration

4. Which of the following is true of the Glomar Challenger? (A) It is a type of submarine. (B) It is an ongoing project. (C) It has gone on over 100 voyages. (D) It made its first DSDP voyage in 1968.

5. The word "extracting" in line 13 is closest in meaning to (A) breaking (B) locating (C) removing (D) analyzing

6. The Deep Sea Drilling Project was significant because it was (A) an attempt to find new sources of oil and gas (B) the first extensive exploration of the ocean bottom (C) composed of geologists from all over the world (D) funded entirely by the gas and oil industry

7. The word "strength" in line 21 is closest in meaning to (A) basis (B) purpose (C) discovery (D) endurance