As the host or co-host in a meeting, you can manage your participants, including muting and unmuting participants to manage background noise and distractions. All participants can also mute or unmute themselves, unless the host has prevented them from unmuting.
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When you schedule a meeting, under meeting options, enable the option "Request permission to unmute participants"
You can enable the Request permission to unmute participants option, which is displayed when scheduling a meeting. 
Selecting this option will display a prompt when participants join the meeting. The prompt will ask for permission to allow the host to mute or unmute them. Permissions, once given, will apply in all meetings scheduled by the same host. 
If a student provides consent to be unmuted, you will have the option to unmute each person individually as needed from the participants list.
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