3.Why is Li Ting unable to finish her term paper on time?
A. Because her computer broke down.
Because she has been sick since last week.
C. Because she hasn’t finished reading the book.
查看答案
4.What is Li Ting going to do?
A. Return the book to Prof. White.
B. Get David to fix her computer.
C. Access her term paper from the computer.
5.What is the last request Li Ting makes?
A. Finishing reading the book.
B. Submitting her term paper.
C. Keeping the book for another week.
以下试剂能作为基准物质的是( )
A. 优级纯的NaOH
B. 化学纯的Co2O3
C. 100℃干燥过的CaO
D. 99.99%纯锌
酸式滴定管不能直接盛装:
A. 氧化性溶液
B. 酸性溶液
C. 中性溶液
D. 碱性溶液
微信支付 
支付宝支付