【简答题】请将与下列食物重量等值的食品交换份数值连起来
【简答题】在经济学中,生产和交换的一般均衡是指两种产品的边际替代率等于这两种产品的()率。
【单选题】蒋某,初产妇,孕40周,临产宫口开全1小时,枕左前位,胎心音110次/分,胎膜已破,羊水浑浊II度,S+3,此时应采取的措施是( )
【判断题】The cash ratio is usually a good indication of the liquidity of the firm.
【单选题】关于供暖系统的设置,以下哪种说法是错误的______
A.
条件许可时,建筑物的集中供暖系统宜分南北朝向设置环路
B.
垂直单、双管供暖系统,同一房间的两组散热器可采用上下接口同侧连接方式
C.
有冻结危险的楼梯间设置的散热器前应设置关断阀
【单选题】Calculate the input impedance for voltage series feedback when the amplifier has = 10 kΩ, amplifier gain is A = -2000, and F= . ( )
A.
input impedance with feedback 10 kΩ
B.
input impedance with feedback 410 kΩ
C.
input impedance with feedback 244 Ω
D.
input impedance with feedback 50 Ω
【单选题】具有吸热和隔热的功能,被称为温室气体的气体是( )
【单选题】When an open occurs on the input of a CMOS gate, the output will ________.
A.
o LOW, because there is no current in an open circuit
B.
go HIGH, since full voltage appears across an open
C.
be treated as if the open input were a HIGH
D.
be unpredictable; it may go HIGH or LOW