皮皮学，免费搜题
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搜题
【单选题】
从大黄中分离5种游离蒽醌,下列分离方法中最佳的是A.
PH梯度萃取法
B.
分步结晶法
C.
柱层析法相结合
D.
制备性薄层层析
E.
氧化铝柱层析
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皮皮学刷刷变学霸
举一反三
【判断题】The writer inquired of the patient in a hospital with questions prepared beforehand.
A.
正确
B.
错误
【简答题】战略控制中的定性控制标准包括哪些?
【单选题】外国旅游者在旅游团的活动结束后,不随口离境,无特殊原因要求延长签证时,导游人员应()
A.
陪同客人到公安局办理延长签证手续
B.
可满足其要求
C.
给予婉拒
D.
请示旅行社
【单选题】When writing an inquiryletter, the writer should first follow the principle of “Frankness”, which meansthat the writer should _____.
A.
make a promise to buy or sell the products inquired about
B.
get to the point and state his information channel and his writing purpose at the very beginning
C.
try to flatter your recipient for more information
D.
make the letter like the one between friends and use courteous words
【判断题】The writer inquired of the patient in a hospital with questions prepared beforehand.( )
A.
正确
B.
错误
【简答题】ARMv7架构的版本中,内核架构有几种款式?分别是什么?
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