Inventions and Discoveries
46. |
The blooding paper absorbs liquids because |
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- A. It is white
- B. It has got small pores
- C. An absorbing chemical is mixed
- D. None of the above
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47. |
The instrument useful for the study of germs is |
|
- A. Periscope
- B. Cardiograph
- C. Microscope
- D. Stethoscope
|
48. |
Lactometer is used to determine |
|
- A. Purity of petrol
- B. Hydrogen in water
- C. Purity of milk
- D. None of these
|
49. |
Numismatics is |
|
- A. Study of coins
- B. Study of stamps
- C. Study of numbers
- D. Study of butterflies
|
50. |
Crude petroleum is refined by the use of |
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- A. Citric acid
- B. Bleaching powder
- C. Sulphuric acid
- D. Hydrochloric acid
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