The incorrect choice about E-mail is ( ).
A. You can compose an e-mail message and send it to another person anywhere.
B. Some e-mail systems are confined to a single computer system or network.
C. It takes at least an hour for an e-mail to arrive at its destination.
D. E-mail is the transmission of messages over communications networks.
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If you want to join Internet Relay Chat discussion ( ).
A. IRC client
B. Internet access
C. IRC host
D. A and B
If you want to join a video-conferencing, the hardware you may need are ( ).
A. Video camera, microphone and speakers.
B. Microphone, speakers and keyboard.
C. Mouse, microphone and speakers
D. Switch, mouse and keyboard
These statements on the below are about SMS and Wireless Communications, which one is correct ( )?
A. SMS enables the transmission of alphanumeric messages between mobile subscribers and internal systems.
B. Messages can be no longer than 160 alpha-numeric characters and must contain no images or graphics in the very first.
C. Once a message is sent, it is received by a Multimedia Messaging Service (MMS).
D. A, B and C
Which type is the most popular for the online courses during the COVID-19 period ( ).
A. Instant Messaging
B. Internet telephone
C. Video-Conferencing
D. Email
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