【单选题】
冷凝压力过高会导致压缩机超载运行,容易损坏_______。___
A. 压缩机零件
B. 冷凝器
C. 蒸发器
D. 节流装置
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答案
A
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空调客车电热采暖时,当通风温度升至_______℃时,熔断器熔断。___
A. 100±5
B. 118±5
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【单选题】
制冷空调是利用容易_______的液体——低压制冷剂,在蒸发和冷凝时的吸热和放热来达到制冷的目的。___
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蓄电池施行准放电时以_______小时率放电。___
A. 3
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电风扇在额定电压下工作一小时,机体表面最高温升不应超过_______℃。___
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蓄电池用蒸馏水中含氯离子不大于_______mg/L。___
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餐车电冰箱大修后,控制箱须保修_______个月。___
A. 6
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某一制冷压缩机型号为4FS7B,S表示_______。___
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25型客车全车最大功率为_______KW。___
A. 3
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压缩机的最高排气温度规定为:R12不超过_______℃。___
A. 100
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【单选题】
高速压缩机一般采用的润滑方式是_______。___
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【单选题】
镍镉蓄电池在常温下贮存一个月,其自放电量约为_______。___
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【单选题】
酸性蓄电池的大修周期是_______年。___
A. 4.5
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【单选题】
KP-2A型控制箱的三相输出线电压为_______V。___
A. 42
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TFX1电子防滑器传感头安装必须密封,传感头与轴头齿轮间隙必须在_______mm之间。___
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【单选题】
B级绝缘材料的极限工作温度是_______℃。___
A. 90
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【单选题】
理论制冷循环中,制冷压缩机吸入的是_______蒸气。___
A. 高温
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【单选题】
在蒸发器中,制冷剂液体在_______温度下沸腾转变为蒸气。___
A. 较低
B. 较高
C. 普通
D. 正常
【单选题】
随着_______蒸气在蒸发器内流动与吸热,制冷剂逐渐蒸发为蒸气。___
A. 干
B. 湿
C. 高温
D. 高压
【单选题】
制冷剂在蒸发器内蒸发温度与蒸发_______相对应,即蒸发压力升高,其蒸发温度也跟着升高。___
A. 环境
B. 条件
C. 压力
D. 速度
【单选题】
制冷剂蒸气进入冷凝器,其自身因受冷却凝结为_______。___
A. 冰
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【单选题】
节流过程是一个_______变化过程。___
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【单选题】
节流元件的作用是将高温高压液体变为低温低压的_______。___
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【单选题】
当高压流体通过小孔时,由于摩擦增加,静压下降,使流体达到_______调节流量的目的。___
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【单选题】
热力膨胀阀是利用蒸发器出口制冷剂的_______自动调节供给蒸发器内制冷剂流量的节流阀。___
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【单选题】
当流体在毛细管内流动时,由于管道摩擦阻力而产生_______。___
A. 温度
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【单选题】
毛细管管径越小或管子越长,则流动的_______就越大。___
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【单选题】
当高压制冷剂液体进入毛细管后,其_______会突然剧增。___
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【单选题】
使用毛细管节流的制冷系统不需要_______,因而充入的制冷剂数量较少。___
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汽液分离器是防止_______制冷剂直接进入压缩机的装置。___
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YZ25K型客车照明控制箱电气原理图中字母代号为_______的电气元件表示熔断器。___
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25K型客车车内的负载按电压可分三种:_______、单相220V交流负载、三相380V交流对称负载。___
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A. 20℃
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25T型客车在A2级修程落成后,满负载运行1h试验,同一接线排各通电接头温度差不得高于_______。___
A. 20℃
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25K型空调客车的空调控制柜[KLC40C-1T1]中6号线是_______控制线。___
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道德是人们用来评价别人和自己言行的标准和尺度
A. 对
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B. Enable URL filtering on the perimeter firewall and add the URls you want to allow to the router's local URL list.
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Refer to the exhibit All ports on switch 1 have a primary vLan of 300 Which devices can host 1 reach?___
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what improvement does EAP-FASTv2 provide over EAP-FAST? ___
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【单选题】
When users login to the Client less Ssl Vpn using https://209.165.201.2/test ,which group policy will be applied?___
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【单选题】
Which user authentication method is used when users login to the Clientless SSLVPN portal using https://209.165.201.2/test?___
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【单选题】
Which statement about the communication between interfaces on the same security level is true?___
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【单选题】
Which feature of the Cisco Email security Appliance can mitigate the impact of snowshoe spam and sophisticated phishing attack?___
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Which type of social-engineering attack uses normal tele phone service as the attack vector?___
A. smishing
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A. exploits
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【单选题】
Referencing the ClA model, in which scenario is a hash- only function most appropriate ?___
A. securing data at rest
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Which ports must be open between a aaa server and a microsoft server to permit Active Directory authentications?___
A. 445 and 389
B. 888 and 3389
C. 636 and 4445
D. 363 and 983
【单选题】
Refer to the exhibit for which reason is the tunnel unable to pass traffic___
A. the tunnel is failing to receive traffic from the remote peer
B. the local peer is unable to encrypt the traffic
C. the ip address of the remote peer is incorrect
D. UDP port 500 is blocked
【单选题】
Which type of attack can exploit design flaws in the implementation of an application without___
A. DHCP starvation attacks
B. low-rate dos attacks
C. application DDos flood attacks
D. application DDoS flood attacks
E. volume-based DDoS attacks
【单选题】
How can you protect CDP from reconnaissance attacks?___
A. Enable dynamic ARP inspection on all untrusted ports.
B. Enable dot1x on all ports that are connected to other switches.
C.
D. isable CDP on ports connected to endpoints.
【单选题】
Which type of attack can exploit design flaws in the implementation of an application without ?___
A. DHCP starvation attacks
B. low-rate dos attacks
C. application DDos flood attacks
D. application DDoS flood attacks
E. volume-based DDoS attacks
【单选题】
Which option is a key security compone nt of and MDM deployment ?___
A. using network-specific installer packages
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【单选题】
Which Firepower Management Center feature detects and block exploits and hack attempts?___
A. Content blocker
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【单选题】
hich description of the nonsecret numbers that are used to start a Diffie- Hellman exchange is ture?___
A. They are preconfigured prime integers.
B. They are large pseudorandom numbers.
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【多选题】
Which two characteristics of an application layer firewall are true?___
A. provides stateful firewal functionality
B. has low processor usage
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【多选题】
Which two devices are components of the BYOD architectural framework?___
A. Nexus 7010 switch
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【多选题】
Which two actions can a zone based firewall take when looking at traffic? ___
A. forward
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【多选题】
n which two situations should you use in-band management?___
A. when management applications need concurrent access to the device
B. when you require administrator access from multiple locations
C. when a network device fails to forward packets
D. when you require ROMMON access
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【多选题】
What are two ways to prevent eavesdropping when you perform device management tasks?___
A. Use an SSH connection.
B. Use SNMPv3
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D. Use SNMP
E. Use in-band management
【多选题】
Which two features are commonly used CoPP and CPPr to protect the control plane? ___
A. QoS
B. traffic classification
C. access lists
D. policy maps
E. class maps
F. Cisco Express Forwarding
【多选题】
Which four tunne ling prot ocols are enabled in the Dfit GrpPolicy group policy ?___
A. Clientless SSL VPN
B. SSL VPN Client
C. PPTP
D. L2TP/IPsec
E. IPsec IKEv1
F. IPsec IKEv2
【多选题】
Which two statements regarding the aSA VPN configurations are correct?___
A. The asa has a certificate issued by an external certificate authority associated to the ASDM TrustPoint1
B. The Default WEBVPNGroup Connection Profile is using the aaa with RADIUS server method
C. The Inside-srvbook mark references the https://192.168.1.2url
D. Only Clientless SSL VPN access is allowed with the Sales group policy
E. Any Connect, IPSec IKEv1, and IPSec IKEv2 VPN access is enabled on the outside interface
F. The Inside -SRV bookmark has not been applied to the Sales group policy
【多选题】
Which three ESP fields can be encrypted during transmission?___
A. Security Parameter Index
B. Sequence Number
C. MAC Address
D. Padding
E. Pad length
F. Next Header
【多选题】
.Which three statements de scribe DHCP spoofing attacks?___
A. They can modify traffic in transit.
B. They are used to perform man- in-the-middle attacks
C. They use ARP poisoning
D. They can access most network devices
E. They protect the ide ntity of the attacker by masking the DHCP address.
F. They are can physically modify the network gateway.
【多选题】
Which statement about the communication between interfaces on the same security level is true?___
A. Interfaces on the same security level require additional configuration to permit interinterface communication
B. Configuring interfaces on the same security level can cause asymmetric routing
C. All traffic is allowed by default between interfaces on the same security level
D. You can configure only one interface on a n individual security level