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【单选题】
超声波在传播的过程中，当遇到两种声阻抗不同的介质界面时，会发生反射和折射，这成为超声波用于临床诊断的物理基础。下列说法正确的是A.
当两种介质声阻抗相差较大时，反射较强，折射较弱
B.
当两种介质声阻抗相近时，反射较强，折射较弱
C.
在空气与人体皮肤交界面上，反射较弱，折射较强
D.
在软组织与颅骨交界面上，反射较弱，折射较强
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【单选题】According to the art dealer, the painting _____ to go for at least a million dollars. [ ]
A.
is expected
B.
expects
C.
expected
D.
is expecting
【单选题】患者女性，慢性肾盂肾炎病史3年，因合并慢性肾衰竭入院治疗，其最早出现的系统症状是
A.
A泌尿系统症状
B.
B消化系统症状
C.
C心血管系统症状
D.
D内分泌系统症状
E.
E神经系统
【单选题】A good many proposals were raised by the delegates, ________ was to be expecte (2003.1/42)
A.
that
B.
what
C.
so
D.
as
【单选题】Which of the following can be used to describe the finding of RV 144?
A.
unexpected
B.
expected
C.
controversial
D.
insignificant
【单选题】They landed safely on the island in the Pacific.Everything went on better than________. [ ]
A.
expec ted
B.
expecting
C.
expectation
D.
to expect
【单选题】患者女性，慢性肾盂肾炎病史3年，因合并慢性肾衰竭入院治疗，其最早出现的系统症状是
A.
泌尿系统症状
B.
消化系统症状
C.
心血管系统症状
D.
内分泌系统症状
E.
神经系统
【简答题】to limit all or most of your study ,business etc to a particular subject or activity
【单选题】Hurricane warnings are issued ______ when winds of force 12 or above are expecte
A.
in all parts of the world
B.
in some parts of the world
C.
from all corners of the world
D.
from every corner of the world
【简答题】The main principles of GATT 19 47 were as follows: (1) Trade 1 was forbidden . Each contracting state had to 2 the same trading privileges and benefits (or most- 3 -nation status) to all other contrac...
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【单选题】患者女性，慢性肾盂肾炎病史3年，因合并慢性肾衰竭入院治疗，其最早出现的系统症状是
A.
A泌尿系统症状
B.
B消化系统症状
C.
C心血管系统症状
D.
D内分泌系统症状
E.
E神经系统
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