After listening to the conversation above, choose the best answer.What are the speakers doing ?
A. Discussing a new project
B. Chatting about their work
C. Participating in a job interview
D. Arranging a sales meeting
Choose the best answer.What does the man's present job involve?
A. Selling audio products
B. Designing speakers
C. Launching new video games
D. Supervising company management
细胞膜在静息情况下,离子通透性最大的是
A. K+
B. Na+
Cl-
D. Ca2+
有机磷农药中毒时,骨骼肌肌无力、肌束抽搐主要是由于
ACh释放减少
B. ACh释放增多
C. 胆碱酯酶活性降低
D. 胆碱酯酶活性增强
微信支付 
支付宝支付