å ¶å®è¯´å°èåï¼å¤§å®¶é½ä¸ä¼éçï¼å®å«æ丰å¯çç»´çç´ Bï¼å ·ææç®ãæ¸ ç解æ¯çåæï¼è¿è½æé«æµæåï¼é¢é²æåã便ç§çåºç°ï¼ä½èåè½å¥½ï¼å´ä¸éååè¿3ç±»é£ç©ä¸èµ·åï¼å¹³æ¶é£ç¨æ¶è¦æ³¨æäºã