局麻药中加入1:200000肾上腺素是指20ml药液中加入肾上腺素()
A.0.1mg
B.0.2mg
C.0.3mg
D.0.4mg
E.0.01mg
参考答案:A
兔子吃草,红狐吃兔,狼吃红狐构成的食物链中,红狐所处的消费者级别及营养级别分别是[ ]
A.次级消费者,第二营养级
B.次级消费者,第三营养级
C.三级消费者,第二营养级
D.三级消费者,第三营养级
—He didn't go to the lecture this morning, did he?
— .Though he was not feeling very well. [ ]
A. No, he didn't
B. Yes, he did
C. No, he did
D. Yes, he didn't