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(1) The most catastrophic weather disaster in the U.S. was a category 4, or extreme, hurricane that struck Galveston, Texas, on Sept. 8, 1900 (2) a 15-foot storm surge killed more than 8,000 people on the low-lying island. (3) In an effort to prevent a similar disaster in the future, the island's elevation was raised about sea level. **(Where the most important supporting details are)
What is sentence two?