【单选题】
JSBXC-850型时间继电器连接端子51-52时，动作时间为_______。[331010103]___
A. 180s±27s
B. 180s±9s
C. 180s±18s
D. 180s±10s
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A
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向继电器线圈供以规定的电压或电流后，切断电源，从断开电源时起至全部动接点离开前接点的时间为_______。[331010103]___
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How does the 802. 1x supplicant communicate with the authentication server？___
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Refer to the exhibit. what is the e ffect of the given configuration？___
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Which command can you enter to configure OSPF to use hashing to authenticate routing updates？___
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Which information can you display by executing the show crypto ipsec sa command？___
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How can you prevent NAT rules from sending traffic to incorrect interfaces？___
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What term can be defined as the securing， control， and identification of digital data？___
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Which a dverse consequence can occur on a network without BPDu guard ?___
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C.
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which attack involves large numbers of ICMP packets with a spoofed source IP address？___
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Which statement about interface and global access rules is true？___
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D. If an interface access rule is applied， the global access rule is ignored
