举一反三
- n. mineral oil that is found under the ground or the sea and is used to produce petrol/gas, paraffin, diesel oil, etc.. A: opponent B: nitrogen C: petroleum D: masterpiece
- Data obtained from the investigations __________ that there is a large amount of oil below the seabed in this area.
- According to Para 3,______per person of the earth’s surface can be used to produce food.
- of all organic chemical is obtained from crude oil and natural gas. A: 80% B: 99% C: 70% D: 79%
- the quality or state of the chemical substance that has a pH values below 7:
内容
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In paraffin section preparation, which of the following chemical reagents is used in the process of dehydration? A: Fixatives B: Ethanol C: Xylene D: Paraffin
- 1
The appearance or quality of light reflected from the surface of a mineral is known as ( ).
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S3. If the temperature at the earth’s surface is 20F, the temperature in a coal mine 500 feet below the surface would be _____________________.
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To _____ a substance means to produce it by means of chemical or biological reactions. ( ) A: synthesize B: detach C: affix D: attach
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Nitrous oxide comes from car exhausts and from chemical fertilizers. Choose the correct definition of the underlined expression according to the context. A: oil used for driving B: waste oil discarded C: gas which is produced by cars D: devices that burn oil