How can I unmute grades for only a particular group of students?
This is only possible if you are using the New Gradebook. If you are seeing the word "Mute" for your assignments it means you are still using the old gradebook which will go away around January 12, 2020. If you'd like to switch to the new gradebook now it is a feature option which depending on how your admins have things set up you might be able to turn on. Go to your course Settings, click on Feature Options and see if you are able to turn it on.
With the new gradebook the term Mute has gone away and now you can Hide and Post grades. If grades for an assignment are hidden, when you post you do have the option of just posting for specific sections as outlined in the guide linked below.
How do I hide grades for an assignment in the New Gradebook?
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