阅读理解 A powerful earthquake struck the northeastern coast of Japan at 2:46 p.m. local time on March 11th. Japan's Meteorological Agency released its first tsunami warnings just three minutes later. The country has one of the best earthquake early warning systems in the world. More than 4,000 Seismic Intensity Meters provide information within two minutes of an earthquake happening. There are also concrete sea walls around much of the Japanese coastline. But these measures proved no match for the powerful earthquake and tsunami. Costas Synolakis is a tsunami expert in the University of Southern California in Los Angeles. He says: 'Japan is one of those most well-prepared countries on earth in terms of tsunami warning. They had a warning. I think what went wrong is that they had not anticipated the size of this event.' He says there are two reasons for this. First, scientists had not expected such a large earthquake. The 9.0 magnitude earthquake was the 4th most powerful earthquake ever recorded worldwide. It was also the worst ever to hit Japan. The tsunami waves reached as high as 13 meters in some areas. Second, Japan's concrete sea walls were not built to handle such high waves.  ' In Sendai(仙台), they were about three meters. At least in that area they were not expecting such a sizeable wave because they would have built a higher seawall.' A tsunami wave can travel as fast as 800 kilometers per hour. To get to higher ground people would often have to travel for many kilometers. This can take more time than a fast traveling tsunami will permit. This is especially true in cases like Japan. The tsunami waves followed almost immediately. Experts say early warning systems will continue to be limited by these facts until earthquakes and tsunamis can be predicted. 1. What is the main idea of the first paragraph? A. A powerful earthquake hit Japan. B. Japan has the best earthquake early warning system. C. Japan can report an earthquake before it happens. D. Better equipment should have been used. 2. According to Costas Synolakis, ________. A. Japan had a warning of such a serious earthquake B. Japan has experienced the worst earthquake worldwide C. the Japanese should have built higher seawalls D. The Japanese were not really prepared for such a disaster 3. According to the writer, why hadn't people got to higher ground? A. Because tsunami doesn't leave much time for them. B. Because they thought the seawalls were reliable. C. Because higher ground can't be reached at all. D. Because didn't know there would be a tsunami. 4. What can we learn from the last paragraph? A. Early warning systems are basically unreliable. B. Earthquakes and tsunamis will soon be predicted. C. We have to accept the imperfect systems for the moment. D. New warning systems will be designed to predict disasters.