若载波uC(t)=UCcosωCt,调制信号uΩ(t)=UΩcosΩt,则普通调幅波的表达式为().
A. uAM(t)=UCcos(ωCt+masinΩt)
B. uAM(t)=UCcos(ωCt+macosΩt)
C. uAM(t)=UC(1+macosΩt)cosωCt
D. uAM(t)=kUΩUCcosωCtcosΩt
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为什么儿童时期膳食纤维的摄入要适量,而中老年时期膳食纤维的摄入要增加?
You are the network administrator for You currently automate backups of the System State data on the servers in your network by using NTBackup. Your manager instructs you to document the procedure for restoring a server from a backup of the System State data. You need to select the correct method for performing a restoration of a backup of the System State data. What should you do?()
A. Run the following command: ntbackup.exe backup /F {"FileName"}
B. Run the following command: ntbackup.exe backup systemstate /F {"FileName"}
C. In Control Panel, open System, and configure the Startup and Recovery settings on the Advanced tab.
D. Use NTBackup interactively.