【单选题】小高在上夜班巡视时,发现一位患者倒在床旁,夜班值班人员只有她一个人。此时针对患者,小高应首先采取的措施是( )。
【单选题】By actual measurement ravens are the most percipient of birds, and on______evidence they seem more______than most other living creatures.
B.
reliable … contumelious
C.
preliminary … retiring
E.
unavailable … intelligent
【单选题】下列说法正确的是
B.
横波是沿水平方向振动的波,纵波是沿竖直方向振动的波
C.
机械波只能在弹性介质 ( 媒质 ) 中传播,而电磁波可以在真空中传播
D.
波源振动的频率就是波的频率,波源振动的速度就是波的传播速度
【单选题】Most of the migratory birds no longer fly across Afghanistan to Pakistan and India because ______.
A.
they change their route from time to time
B.
some birds have collapsed while flying
C.
they have been threatened by the bombs dropped on the country
D.
they are seared by the big animals in the mountains
【单选题】Most of the migratory birds no longer fly across Afghanistan to Pakistan and India because ______.
A.
they change their route from time to time.
B.
some birds have collapsed while flying.
C.
they have been threatened by the bombs dropped on the country.
D.
they are scared by the big animals in the mountains.
【单选题】下列说法正确的是
B.
横波是沿水平方向振动的波,纵波是沿竖直方向振动的波
C.
机械波只能在弹性介质(媒介)中传播,而电磁波可以在真空中传播
D.
波源振动的频率就是波的频率,波源振动的速度就是波的传播速度
【单选题】下列说法正确的是( )。
B.
横波是沿水平方向振动的波,纵波是沿竖直方向振动的波
C.
机械波只能在弹性介质(媒质)中传播,而电磁波可以在真空中传播
D.
波源振动的频率就是波的频率,波源振动的速度就是波的传播速度