由题意x+8﹣7﹣9+3=62.6,
解得x=67.6cm.
答:河里水位初始值为67.6cm.
----The radio says that a new typhoon (台风) is coming.
---- Really, All the ____ (渔民)on the sea must come back.
如果∠a是等边三角形的一个内角,那么cosa的值等于( ).