地下水有何特点?
参考答案:
地下水的特点:悬浮杂质少、浑浊度低、有机物和细菌含量少;含盐量和硬度高,直接受污染的机会少。
— I just can't stop worrying about the result of the job interview.
— _____. There's nothing you can do now but wait. [ ]
A. Relax
B. Go ahead
C. Go for it
D. Good luck
消毒与灭菌的主要区别是能否杀灭
A.非致病微生物B.病原微生物C.繁殖体D.芽孢E.鞭毛