14. The discovery that electricity could produce magnetism __________ in 1820 by the Danish physicist, Hans Christian Oerested. a. by accident b. was an accident c. was made by accident d. by accident was
C
2. __________ more than 2,000 minerals are known, nearly all rocks are formed from seven mineral groups. a. Although b. However c. Despite d. Since A
A
10. __________ an organism to become a fossil. a. Rarely b. It is rare c. Rare is d. It is rare for
D
9. __________ food we eat lacks minerals, then the body can use the stores from its bones for more urgent needs. a. As the b. If the c. The d. Since
B
8. __________ the world’s most successful artificial language. a. As Esperanto is b. That Esperanto c. It is Esperanto d. Esperanto is
D
11. Among sea horses, __________ carries and hatches the eggs in a special breeding pouch. a. it is the male which b. the male it c. it is the male d. the male who
A
3. Alexander Graham Bell worked with deaf students before __________ the first telephone in 1876. a. designed b. was designed c. to design d. designing
D
5. Food of animal origin generally supply greater amounts of iron to the diet than __________ a. are foods of plant origin b. foods of plant origins c. do foods of plant origin d. plant origin foods
C
15. Digital systems work first by changing quantity and then __________ into strips of numbers. a. convert the measurements b. the measurements convert c. to convert the measurements d. converting the measurements
D
1. The behavior of many volcanoes __________ very difficult to predict, especially the more explosive types. a. are b. is c. that d. being
B
6. __________ energy for growth or repair, a plant must carry out photosynthesis. a. To obtain b. It obtains c. It is obtaining d. Obtaining
A
7. Nicotine, __________ found in tobacco, is named after the French diplomat Jean Nicot. a. it is a chemical compound b. is a chemical compound c. a chemical compound d. chemical compound is
C
16
A
13. Scientists have discovered that the jellylike material in cells __________ proteins and other substances. a. is actually a complex mixture b. it is actually a complex mixture c. actually is a complex mixture of d. that actu
C
12. __________ will be increasingly used as a source of petrochemicals when oil begins to run out. a. No matter coal b. No doubt coal c. If coal d. That coal
B
4. An enzyme works by coming in contact with a particular substance, __________ with it, and changing it. a. combines b. combining c. it combines d. to combine
B