17. Where is the origin of an earthquake?
a. Epicenter b. focus c. fault d. fault line
18. What instrument is used to study earthquakes and seismic waves?
a. resistor b. radiograph C. seismograph d. all of these
19. Where do most of the world's strong earthquakes occur?
a. divergent plate boundaries c. Japan and Indonesia b. ring of fire d. Mediterranean- Himalayan seismic belt
20. Which of the following seismic waves are not transmitted through liquid? a. primary waves b. secondary waves c. surface waves d. transverse waves​