C.the name of a blue whale

　D.a famous dinosaur

11There are not many kinds of whales left because 　　　.

　A. they don't lay eggs

　B.people have killed them

　C.they live in the ocean

　D.there are laws against them

12The passage is mainly about　　　.

A.the world's biggest animal

B.lots of stories about whales

C.laws to stop people killing whales

D.the differences between dinosaurs and whales

There are a lot of strong tsunamis because of the size of the ocean and large earthquakes there.In open seas tsunamis are only one or two metres high.But when they are near the land,they can be as high as six or seven metres.

Houses and cars near the sea can be swept away by these big waves.Because tsunamis move fast and can travel to the other side of the sea within one day,they may affect a lot of places.

Do you know the worst tsunamis in history in the world?Look through the following list.

　　Worst tsunamis

Location Year Deaths Indian Ocean 2004 150,000 South China Sea 1782 40,000 South Java Sea 1883 36,500 Tokaido-Nankaido,Japan 1707 30,000 Sartriku,Japan 1896 26,360 Northern Chile 1868 25,674