【单选题】Which of the followings is NOT the topic of the meetings between the two presidents?
【单选题】下列有关 的说法中不正确的是 [ ]
B.
该有机物的化学式为C 19 H 18 N 3 O 2
D.
该有机物既能与溴水反应,又能与碳酸钠溶液反应
【单选题】有机物A的结构简式如右图,下列关于A的性质叙述中,错误的是
C.
A与氢氧化钠溶液完全反应时,两者物质的量之比是1∶3
【简答题】设由[0,1]中取n个可测子集E 1 ,E 2 ,…,E n 假定[0,1]中任一点至少属于这n个集中的P个,试证:这n个子集中必有一集,它的测度不小于5。
【单选题】有机物A的结构简式如图,下列关于A的性质叙述中,错误的是( )
C.
A与氢氧化钠溶液完全反应时,两者物质的量之比是1:3
【单选题】下列有机物中,在不同条件下,既能发生水解反应和消去反应,又能发生酯化反应并能与金属钠反应放出氢气的是( )
【单选题】Which of the following is NOT the common feature of eBay and the two new services, WhipCar and RelayRides?
A.
The feasibility of their service is/was doubted of.
B.
All of them serve as an intermediary.
C.
All of them offer auction services.
D.
All of them are operated online.
【单选题】Which of the following is NOT the celebration of the two special days?
B.
Cleaning parents' house.
C.
Visiting the cemetery.
【单选题】下列有机物中,不能发生水解的是 A.CH 3 COOCH 3 B. CH 3 CONH 2 C. CH 3 COOH D.A、B、C均不能