相关试题
【单选题】
32在Keil C里，中断子程序与函数又何不同？___
A. 中断子程序不必声明
B. 函数不必声明
C. 中断子程序必须有形式参数
D. 中断子程序一定会有返回值
【单选题】
33若要同时启用INT0及INT1中断功能，则应如何设置？___
A. TCON=0×81
B. IE=0×85
C. IP=0×83
D. IE=0×03
【单选题】
35在8×51的Timer里，若使用Mode 0，其最大计数值为多少个机器周期？___
A. 65636
B. 8192
C. 1024
D. 256
【单选题】
36在12MHz的8×51系统里，哪一种方式一次可定时5ms？___
A. Mode 0及Mode 1
B. Mode 1及Mode 2
C. Mode 2及Mode 3
D. Mode3及Mode 1
【单选题】
37若要让Timer作为外部计数只用，应如何设置？___
A. Gate=0
B. Gate=1
C. C/=0
D. C/=1
【单选题】
39下列哪个不是8×51所提供的省电方式？___
A. PD方式
B. IDL方式
C. LP方式
D. 待机方式
【单选题】
89S51的看门狗有何作用？___
A. 重复执行程序
B. 找回遗失数据
C. 复位系统
D. 防止中毒
【单选题】
41若要启用WDT，则应依次填入WDTRST寄存器哪些数据？___
A. 0xe1、0xe2
B. 0xe1、0x1e
C. 0x1e、0xe1
D. 0x10、0x01
【单选题】
8×51的定时器，在下列哪种方式下具有自动加载功能？___
A. Mode0
B. Mode1
C. Mode2
D. Mode3
【单选题】
45下列哪种AD转换器的转换速度比较快？___
A. 双斜率型AD转换器
B. 比较型AD转换器
C. 连续计数式AD转换器
D. 逐渐接近式AD转换器
【单选题】
46下列哪种AD转换器的精密度比较高？___
A. 双斜率型AD转换器
B. 比较型AD转换器
C. 连续计数式AD转换器
D. 逐步逼近式AD转换器
【单选题】
47对于8×8 LED点阵而言，其中的LED个数及引脚各为多少？___
A. 64、16
B. 16、16
C. 64、12
D. 32、12
【单选题】
48在共阳极型8×8 LED点阵里，其阳极如何连接？___
A. 各行阳极连接到行引脚
B. 各列阳极连接到列引脚
C. 各行阳极连接到列引脚
D. 各列阳极连接到行引脚
【单选题】
49在共阳极型8×8 LED点阵里，其阴极如何连接？___
A. 各行阴极连接到行引脚
B. 各列阴极连接到列引脚
C. 各行阴极连接到列引脚
D. 各列阴极连接到行引脚
【单选题】
50双色8×8 LED点阵的列引脚与行引脚各位多少？___
A. 12、12
B. 8、16
C. 16、8
D. 24、8
【单选题】
___的方向规定由高电位点指向低电位点。
【单选题】
三相电动势到达最大的顺序是不同的，这种达到最大值的先后次序，称三相电源的相序，相序为U-V-W-U，称为___。
【单选题】
电路的作用是实现能量的传输和转换、信号的___和处理。
【单选题】
电阻器反映导体对电流起阻碍作用的大小，简称___。
A. 电动势
B. 功率
C. 电阻率
D. 电阻
【单选题】
___反映了在不含电源的一段电路中，电流与这段电路两端的电压及电阻的关系。
A. 欧姆定律
B. 楞次定律
C. 部分电路欧姆定律
D. 全欧姆定律
【单选题】
并联电路中的总电流等于各电阻中的___。
A. 倒数之和
B. 相等
C. 电流之和
D. 分配的电流与各电阻值成正比
【单选题】
串联电路中流过每个电阻的电流都___。
A. 电流之和
B. 相等
C. 等于各电阻流过的电流之和
D. 分配的电流与各电阻值成正比
【单选题】
___的一端连在电路中的一点，另一端也同时连在另一点，使每个电阻两端都承受相同的电压，这种联结方式叫电阻的并联。
A. 两个相同电阻
B. 一大一小电阻
C. 几个相同大小的电阻
D. 几个电阻
【单选题】
___的电阻首尾依次相连，中间无分支的联结方式叫电阻的串联。
A. 两个或两个以上
B. 两个
C. 两个以上
D. 一个或一个以上
【单选题】
电流流过负载时，负载将电能转换成___。
A. 机械能
B. 热能
C. 光能
D. 其他形式的能
【单选题】
电功的数学表达式不正确的是___。
A. W=Ut/R2t
B. W=UIt
C. W=U2t/Rt
D. W=I2Rt
【单选题】
测量电压时，电压表应与被测电路___。
【单选题】
测量电流时,万用表的接线方法与直流电流表一样，应把万用表___在电路中。测量直流电压时，应把万用表与被测电路并联。
【单选题】
串联电路中各电阻两端电压的关系是___。
A. 各电阻两端电压相等
B. 阻值越小两端电压越高
C. 阻值越大两端电压越高
【单选题】
确定正弦量的三要素为 ___。
A. 相位、初相位、相位差
B. 最大值、频率、初相角
C. 周期、频率、角频率
【单选题】
当电压为5V时,导体的电阻值为5欧,那么当电阻两端电压为2V时,电阻值为___欧。
【单选题】
对称负载接成星形时,三相总电流___。
A. 等于零
B. 等于其中一相电流的三倍
C. 等于其中一相电流。
【单选题】
一段有源支路如图1所示，AB两端的电压UAB为___。
A. 10 V
B. —2V
C. 2V
D. —10V
【单选题】
如图2电路中，等效电阻=___
A. 150Ω
B. 900Ω
C. 600Ω
D. 100Ω
【单选题】
电流表的读数是4A，则电路中电流表的读数是 ___
【单选题】
在R、L、C串联电路中，已知＝3Ω，＝5Ω，＝8Ω，则电路的性质为 ___。
A. 感性
B. 容性
C. 阻性
D. 不能确定
【单选题】
工业生产中大量的设备均为感性负载，功率因数往往很低，常采取___的方法来提高电网的功率因数。
A. 并联电容
B. 串联电容
C. 串联电感
D. 并联电感
【单选题】
交流电压表及电流表指示的数值是___
A. 平均值
B. 有效值
C. 最大值
D. 瞬时值
推荐试题
【单选题】
What is the minimum number of hosts that must contribute capacity to a non-ROBO single site VMware vSAN cluster?___
【单选题】
Which guest operating system supports PVRDMA?___
A. Windows (32-Bit)
B. Linux (32-Bit)
C. Windows (64-Bit)
D. Linux (64-Bit)
【单选题】
What is the correct way to replace the certificate on an existing vCenter Server that is part of a vCenter HA configuration?___
A. Put the vCenter HA in Maintenance mode, replace the certificate, exit Maintenance mode.
B. Shut down Passive and Witness nodes and replace the certificate on the Active node.
C. Remove the Passive and Witness nodes, replace the certificate, reconfigure the cluster.
D. Replace the certificate while all nodes are participating in the cluster.
【单选题】
The vSphere Data Protection performance analysis results in the “Conditionally Passed” status. What can cause this condition?___
A. The results did not meet the minimum performance expectations.
B. The read, write, and seek tests were successful.
C. The read and write tests were successful but the seek test failed.
D. The read and write tests were successful but the seek test skipped.
【单选题】
A vSphere Administrator wants to reserve 0.5 Gbps for virtual machines on each uplink on a disturbed switch that has 10 uplinks. What is the quota that should be reserved for the network resource pool?___
A. 10 Gbps
B. 5 Gbps
C. 100 Gbps
D. 0.5 Gbps
【单选题】
A vSphere administrator manages a cluster which includes critical and non-critical virtual machines. The cluster requires different permissions for contractors and non-contractors. How can the administrator exclude the contractor group from some of the critical VMs?___
A. Apply permission for both contractors and non-contractors on the cluster level.
B. Apply permission for both contractors and non-contractors on the cluster level. Remove permission on the critical VMs for contractors.
C. Remove permission for contractors on the cluster level. Apply permission on the critical VMs for noncontractors.
D. Apply permission for both contractors and non-contractors on the VMs. Remove permission on the critical VMs for contractors.
【单选题】
In an ESXi 6.5 cluster only "NFS datastore has running or registered virtual machines" returns. A vSphere HA cluster with four hosts has admission control configured to tolerate one host failure. Which statement is true if a fifth host is added?___
A. CPU and Memory capacity will be set to 50%.
B. CPU and Memory capacity will be set to 30%.
C. CPU and Memory capacity will be set to 25%.
D. CPU and Memory capacity will be set to 20%.
【单选题】
Which command can be run to troubleshoot connectivity problems with vmkernal network interfaces?___
A. esxcli network
B. vmkping
C. net-status
D. vicfg-vmknic
【单选题】
What counter should an administrator check to determine if a virtual machine is ballooning?___
A. swapinRate
B. vmmemctltarget
C. swapped
D. vmmemctl
【单选题】
By default, how often is the vCenter vpx user password automatically changed?___
A. 15 days
B. 60 days
C. 30 days
D. 45 days
【单选题】
Which metric in the Exhibit would identify high latency for a virtual machine operating system?___
A. QAVG/cmd
B. KAVG/cmd
C. DAVG/cmd
D. GAVG/cmd
【单选题】
What VM Monitoring setting would ensure that the failure interval for a virtual machine is defined as 120 seconds?___
A. High
B. Normal
C. Low
D. Medium
【单选题】
The business managers have asked the IT administrator to ensure configuration compliance in the vSphere infrastructure. The IT administrator wants to use Host Profiles to accomplish this, but is unable to do so. Why is the administrator unable to use Host Profiles?___
A. The infrastructure uses a vSphere Standard license.
B. The infrastructure has servers with various CPU families.
C. The user has only the “Administrator” role.
D. Host Profiles apply only to storage settings.
【单选题】
What is the result of a “Consolidate” action on a virtual machine?___
A. All snapshots on the virtual machines will be deleted.
B. The virtual machine will be reverted to its last snapshot.
C. Redundant delta disks will be combined and deleted.
D. A new snapshot with memory state will be created.
【单选题】
A Telco customer is implementing NFV using vSphere as the virtualization platform. Which feature can help achieve a high packet rate with lower CPU consumption?___
A. Network I/O Control
B. SplitRX
C. ERSPAN
D. LACP
【单选题】
What is the VMware-recommended best practice for Fibre Channel zoning?___
A. soft zoning
B. single-initiator-multiple-target zoning
C. single-initiator zoning
D. single-initiator-single-target zoning
【单选题】
How can a vSphere administrator ensure that a set of virtual machines run on different hosts in a DRS cluster?___
A. Use a VM-Host affinity rule.
B. Add the VMs to a vApp.
C. Use a VM-VM affinity rule.
D. Place the VMs in different folders.
【单选题】
vCenter Server Appliance Instance can be backed up using which Client Interface?___
A. vSphere Client Interface
B. vSphere Web Client Interface
C. VMware Host Client Interface
D. Virtual Appliance Management Interface
【单选题】
What tool can capture network traffic at the uplinks, or vSwitch, or virtual port levels?___
A. tcpdump-uw
B. wireshark
C. pktcap-uw
D. pcap
【单选题】
Which storage feature always requires the use of third-party software on ESXi?___
A. Hardware Acceleration for NAS devices
B. VVOL
C. Hardware Acceleration for Block
D. evices
【单选题】
An ESXi host's VMCA-Signed certificate has expired. How can the certificate be renewed?___
A. In the vSphere Web Client, browse to the host in question. Click the Manage tab and select settings. Select System and click Certificate, then click the Renew button.
B. In the vSphere Web Client, browse to the host in question. Click the Manage tab and select settings. Select System and click Certificate, then click the Refresh CA Certificates button.
C. Run the command /sbin/generate-certificates on the affected host.
D. Disconnect the host from vCenter Server and reconnect it.
【单选题】
Which is the correct order for upgrading vSphere components?___
A. vCenter Server, ESXi hosts, VMware Tools, Virtual Machine hardware
B. VMware Tools, Virtual Machine hardware, ESXi hosts, vCenter Server
C. vCenter Server, Virtual Machine hardware, VMware tools, ESXi hosts
D. ESXi hosts, vCenter Server, Virtual Machine hardware, VMware Tools
【单选题】
Which iSCSI initiator type can be used with any network interface card?___
A. Software iSCSI initiator
B. Software FCoE adapter
C. Hardware Independent iSCSI initiator
D. Hardware Dependent iSCSI initiator
【单选题】
An administrator is attempting to power on a virtual machine with 32GB of memory. The operation fails with the following error: <Could not power on VM: No space left on device> <Checking the space on the virtual machine's datastore, there is 30GB free.> Which action would allow the VM to power on?___
A. Set a 2GB memory reservation on the VM.
B. Mount the virtual disk from the affected VM on to another virtual machine and free up space from within the OS.
C. Enable vSphere HD admission control on the cluster in which the VM resides.
D. Set a 2GB memory limit on the VM.
【单选题】
An administrator attempts to manually reclaim space on thin-provisioned VMFS6 volumes but finds that no additional space is being recovered. Which could be causing this?___
A. vSphere 6.5 does not support manual UNMAP.
B. The manual UNMAP operation has been moved to the vSphere web client.
C. The VASA version is use is incompatible.
D. UNMAP is automated for VMFS6.
【单选题】
An administrator has upgraded to vSphere 6.5 and also wants to use Kerberos authentication for NFS. Which can be done to the existing NFSv3 volumes to enable this feature?___
A. Perform a storage rescan on VMFS volumes.
B. Unmount the NFSv3 datastore, and then mount as NFSv4.1 datastore.
C. Nothing. All NFSv3 mounted datastores are upgraded automatically during vSphere upgrades.
D. Perform a scan of new storage devices.
【单选题】
An administrator wants to restore the vCenter Server Appliance 6.5 from backup. Where can this be accomplished?___
A. from the ESXi Host Client
B. from the VMware vSphere Appliance Management Interface
C. from within the VMware vSphere Web Client
D. from the vCenter Server Appliance Installer
【单选题】
The administrator wants to power on VM-K2, which has a 2GHz CPU reservation. VM-M1, VM-M2, and VM-K1 are all powered on. VM-K2 is not powered on. The exhibit shows the parent and child resource reservations. If Resource Pool RP-KID is configured with an expandable reservation, which statement is true?___
A. VM-K2 will be unable to power on because there are insufficient resources.
B. VM-K2 will be able to power on since resource pool RP-KID has 2GHz available.
C. VM-K2 will be unable to power on because only 2GHz are reserved for RP-KID.
D. VM-K2 will receive resource priority and will be able to power on this scenario.
【单选题】
Which is the block size on the VMFS6 datastore?___
A. All small and large file blocks are 8MB.
B. All small and large file blocks are 1MB.
C. Small file blocks are 512KB. large file blocks are 64MB.
D. Small file blocks are 1MB, large file blocks are 512MB.
【单选题】
When installing vCenter Converter Standalone, why must an administrator perform a client-server installation instead of a local installation?___
A. to manage conversion tasks remotely
B. to convert virtual machines as well as physical machines
C. to allow installation of the Converter agent on remote source machines
D. to hot clone physical or virtual machines
【单选题】
Which is required by vCenter Converter Standalone to convert a physical Red Hat Enterprise Linux 7 machine to a virtual machine?___
A. The Linux machine must be powered off.
B. The Linux machine must have the SSH daemon started.
C. The Linux machine must use a static IP address.
D. The Linux machine must have a fully-qualified domain name.
【单选题】
An administrator is troubleshooting network communications between a vCenter Server and an ESXi 6.5 host. Which log shows the related events between these components?___
A. /var/log/fdm.log
B. /var/log/vpxa.log
C. /var/log/hostd.log
D. /var/log/auth.log
【单选题】
An administrator has recently upgraded from vSphere 6.0 to 6.5, and can no longer see the software iSCSI named vmhba33. Which could be the reason for this?___
A. The upgrade has changed the vmhba name.
B. vSphere 6.5 automates iSCSI configurations.
C. vSphere 6.5 no longer supports software iSCSI.
D. The upgrade has deleted the vmhba.
【单选题】
An administrator is trying to vMotion a VM from his datacenter to a recovery site. Which is the maximum allowed RTT (Round-Trip Time) latency between source and destination host?___
A. 100 milliseconds
B. 150 milliseconds
C. 15 milliseconds
D. 10 milliseconds
【单选题】
Which is required for configuring iSCSI Software Adapter network port binding?___
A. VMkernel of the iSCSI traffic must be load balanced using Route based on IP Hash algorithm.
B. VMkernel of the iSCSI traffic must be load balanced using Route based on Source Virtual Port ID algorithm.
C. VMkernel of the iSCSI traffic must be load balanced using Route based on Source MAC Hash algorithm.
D. VMkernel of the iSCSI traffic must be bound to only one active network adapter.
【单选题】
In vSphere Data Protection 6.1, which is the function of a Backup Verification job?___
A. None. Backup Verification job is not a feature of vSphere Data Protection
B. It is a manual task -Power it on -Verify the guest OS -Check started applications
C. It is an automatic process -Restore a virtual machine -Power it on -Verify that the guest OS is booted by communicating with the Backup Verification agent
D. It is an automatic process -Restore a virtual machine -Power it on -Verify that the guest OC is booted by detecting the VMware ToolsTM "heartbeats"
【单选题】
An administrator has enabled vSphere Distributed Switch Health Check. The hosts connected to that Distributed Switch all display an alert:< vSphere Distributed Switch MTU supported status > .The administrator has all of the VMkernel ports MTU sizes set to 1600. Which action will remedy this problem?___
A. Configure the Distributed Switch to MTU 9100.
B. Disconnect and reconnect the physical network cable.
C. Configure the physical switch to MTU 1600.
D. Disable the Distributed Switch MTU.
【单选题】
Which Host Profile Subprofile configuration is used to configure firewall settings for ESXi hosts?___
A. Advanced Configuration Settings
B. General System Settings
C. Security
D. Networking
【单选题】
Where would a vSphere administrator find general vCenter Server logs on a vCenter Server Appliance?___
A. /var/log/vmware/vpxd/
B. /var/log/messages
C. /etc/vmware-vpx/
D. /var/log/vmware/vsan-health/
【单选题】
An administrator wishes to enable network port mirroring based on source port. Which feature should be enabled?___
A. vSphere standard switch port
B. ERSPAN
C. NSX Virtual Wire
D. VLAN
