ÌâÄ¿ÄÚÈÝ
×î½ü¡¶ÃÀ¹ú¿ÆÑ§ÔºÔº¿¯¡··¢±íÁ˹ØÓÚÈËÌåÌåÏãµÄÑо¿ÎÄÕ£¬ÎÄÕ³ÆÈ˵ÄÌåζÖдæÔÚÁ½ÖÖÃûΪ¡°AND¡±ºÍ¡°EST¡±µÄºÉ¶ûÃÉ¡£¹ØÓÚ¡°AND¡±ºÍ¡°EST¡±µÄÏÂÁÐ˵·¨ÖÐÕýÈ·µÄÊÇ

(Ìáʾ£º
)
(Ìáʾ£º
| A£®¡°AND¡±ºÍ¡°EST¡±»¥ÎªÍ¬·ÖÒì¹¹¹ØÏµ |
| B£®¡°EST¡±²»ÊôÓÚ·¼ÏãÌþ£¬¡°AND¡±²»ÊôÓÚ·¼ÏãÌþ |
| C£®¡°AND¡±ºÍ¡°EST¡±Á½Õß·Ö×Óʽ֮²îΪCH3 |
| D£®¡°AND¡±ºÍ¡°EST¡±¾ù¿ÉÒÔÓëäåË®·¢Éú·´Ó¦ |
BD
A´í£¬Í¬·ÖÒì¹¹ÌåΪ·Ö×ÓʽÏàͬ¶ø½á¹¹Ê½²»µÄ»¯ºÏÎ¡°AND¡±ºÍ¡°EST¡±µÄ·Ö×Óʽ²»Í¬£¬²»ÊôÓÚͬ·ÖÒì¹¹Ì壻BÕýÈ·£¬·¼ÏãÌþÊÇÖ¸º¬Óб½»·µÄÌþ£»C´í£¬¡°ANDµÄ·Ö×ÓʽΪ
¡±ºÍ¡°ESTµÄ·Ö×ÓʽΪ
¡±Á½Õß·Ö×Óʽ֮²îΪCH4£»DÕýÈ·£¬Á½·Ö×ӽṹÖÐÔöÓÐ̼̼˫¼ü£»
Á·Ï°²áϵÁдð°¸
Ïà¹ØÌâÄ¿