2；1；1；3；2；2
低渗性脱水时，一般不会出现（）
A.明显口渴
B.恶心、呕吐、肌肉痉挛
C.尿相对密度低
D.尿内Cl-很少
E.血清Na+降低
（）is not a job of the radar antenna.
A.To receive the high-frequency pulses from the transmitter
B.To focus the pulses into a beam，and send them into space
C.To pick up reflected pulses coming from objects that have been struck by the beam
D.To reflect microwaves
