II. Read the passage and answer the questions. (1.0 pt)
Tsunamis are giant sea waves. These waves are quite different from storm
surges. They are also referred to by the general public as tidal waves although
they have nothing to do with tides. Scientists often refer to them as seismic sea
waves, which is far more appropriate because they are often the result of
undersea seismic activity.
Tsunamis can be caused when the sea floor suddenly moves, during an
underwater earthquake or volcano, and the water above the moving earth is
suddenly displaced. This sudden shift of water sets off a series of waves. These
waves can travel great distances, at speeds close to 700 kilometers per hour. In
the open ocean, tsunami waves are not very high, often no more than one or two
metres. It is when they hit the shallow waters near the coast that they increase in
height, possibly up to 40 metres.
1. What are tsunamis?
2. Do tsunamis have anything related to tide.?...............
3. When can tsunamis happen?
4. Where are tsunamis waves higher, in the open ocean or in the shallow water?