What is the minimum period of time that the air supply for a self-contained breathing apparatus is required to last?________.A.10 minutesB.20 minutesC.30 minutesD.90 minutes
What is the minimum period of time that the air supply for a self-contained breathing apparatus is required to last?________.
A.10 minutes
B.20 minutes
C.30 minutes
D.90 minutes
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When voltage and current developed in an AC circuit reach their peak values at the same time, the power factor is _____.A.laggingB.leadingC.maximumD.minimum
The majority of nurses are women, but in the higher ranks of the medical professionwomen are in a__________.A.minorityB.scarcityC.rarityD.minimum
在 Windows 中，运行（请作答此空）命令得到下图所示结果。以下关于该结果的叙述中，错误的是（）。Pinging 59.74.111.8 with 32 bytes of data:Reply from 59.74.111.8: bytes=32 time=3ms TTL=60Reply from 59.74.111.8: bytes=32 time=5ms TTL=60Reply from 59.74.111.8: bytes=32 time=3ms TTL=60Reply from 59.74.111.8: bytes=32 time=5ms TTL=60Ping statistics for 59.74.111.8: Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),Approximate round trip times in milli-seconds: Minimum = 3ms, Maximum = 5ms, Average = 4msA.ipconfig/allB.pingC.netstatD.nslookup
在 Windows 中，运行（ ）命令得到下图所示结果。以下关于该结果的叙述中，错误的是（ ）。Pinging 59.74.111.8 with 32 bytes of data:Reply from 59.74.111.8: bytes=32 time=3ms TTL=60Reply from 59.74.111.8: bytes=32 time=5ms TTL=60Reply from 59.74.111.8: bytes=32 time=3ms TTL=60Reply from 59.74.111.8: bytes=32 time=5ms TTL=60Ping statistics for 59.74.111.8: Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),Approximate round trip times in milli-seconds: Minimum = 3ms, Maximum = 5ms, Average = 4msA.ipconfig/allB.pingC.netstat D.nslookup
在 Windows 中，运行（请作答此空）命令得到下图所示结果。Pinging 59.74.111.8 with 32 bytes of data:Reply from 59.74.111.8: bytes=32 time=3ms TTL=60Reply from 59.74.111.8: bytes=32 time=5ms TTL=60Reply from 59.74.111.8: bytes=32 time=3ms TTL=60Reply from 59.74.111.8: bytes=32 time=5ms TTL=60Ping statistics for 59.74.111.8: Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),Approximate round trip times in milli-seconds:Minimum = 3ms, Maximum = 5ms, Average = 4ms）A.ipconfig/allB.pingC.netstatD.nslookup
8、基于initial语句产生普通时钟信号， parameter clk_period = 10; reg clk; initial begin clk = 0; ________________; endA．always #(clk_period/2) clk = ~clkB．forever #(clk_period/2) clk = ~clkC．always #(clk_period) clk = ~clkD．forever #(clk_period) clk = ~clk
基于initial语句产生普通时钟信号， parameter clk_period = 10; reg clk; initial begin clk = 0; ________________; endA．always #(clk_period/2) clk = ~clkB．forever #(clk_period/2) clk = ~clkC．always #(clk_period) clk = ~clkD．forever #(clk_period) clk = ~clk
在端口PHI1创建时钟周期为10，上升在5.0，下降在9.5A．create_clock “PHI1” –period 10 –waveform {5.0 9.5}B．create_clock “PHI1” period 10 –waveform {5.0 9.5}C．create_clock “PHI1” period 10 waveform {5.0 9.5}D．create_clock “PHI1” –period 10 –waveform {1 2}
以下关于VDB函数的语法正确的是（）。A．VDB（cost，salvage，life，period，factor）B．VDB（cost，salvage，life，period，month）C．VDB（cost，salvage，life，per）D．VDB（cost，salvage，life，start-period，end-period，factor，no-switch）