题目

Maybe ten-year-old Elizabeth put it best when she said to her father. But. Dad. you can't be healthy if you're dead.   Dad. in a hurry to get home before dark so he could go for a run. had forgotten to wear his safety belt-a mistake 75% of the US population make every day The big question is why.   There have been many myths about safety belts ever since heir first appearance in cars some forty years ago. The following are three of the most common.   Myth Number One: It's best to be thrown clear of a serious accident.   Truth: Sorry, but any accident serious enough to throw you 在△ABC中，角A,B,C所对的边分别为a,b,c, △ABC的面积S=(1)求角C的大小（2）若c=1，求△ABC周长L的取值范围