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Considerations for Joining by Phone as the Host
The number of phones that can connect to a Zoom meeting or webinar is determined by account type and add-on assigned to the user account.
Pro User: 100 Dial In Users
Your Lehigh zoom account allows for up to 300 users.
Phone controls for meeting host
If you have entered the Host Key to start the meeting, you will have host controls available to you by entering DTMF tones on your dial pad. To hear all available commands, enter ** on your phone.
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https://support.zoom.us/hc/en-us/articles/201362803-What-is-Scheduling-Privilege-