21. Which of the following is/are the correct charateristic (s) of primary seismic wave ?

1. 1. It is longitudinal and compressional wave

   
   
   

   2. It is analogous to sound waves

   
   
   

   3. It travels with faster speed through solids but slowly through liquids

   
   
   

   4. All the above three

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: D

   NA

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22. Which of the following statements best describes the usefulness of volcancity ?

1. 1. A violent volcanic eruption represents the release of an enormous amount of energy

   
   
   

   2. The high density of population in parts of java is dependent on agriculture

   
   
   

   3. Some volcanoes are dorment

   
   
   

   4. Fissure eruption are usually non-violent

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: B

   NA

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23. Which one of the following best describes the world distribution of active and recently active volcanoes?

1. 1. They are found in association with young fold mountain chain

   
   
   

   2. They occur in river flood plains

   
   
   

   3. They are associated with old eroded mountain chains

   
   
   

   4. They are located on the western sides of continents

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   NA

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24. The number indicating the intensity of an earthquake on a Richter scale range between

1. 1. 1 to 7

   
   
   

   2. 1 to 8

   
   
   

   3. 1 to 9

   
   
   

   4. 1 to 12

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: C

   NA

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25. Ema is an example of

1. 1. Active volcano

   
   
   

   2. Dormant volcano

   
   
   

   3. Extinct volcano

   
   
   

   4. Plateau in a volcano region

   
   
   

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1. View Hint View Answer Discuss in Forum

   NA

   Correct Option: A

   NA

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