Question- How do I send an email to a group of people without letting them see each others email addresses?
Answer – You need to add the email addresses to the blind copy line (BCC) not the to or CC line to accomplish this.
However in most email programs the BCC line isn’t shown by default when you compose the email which is why many people miss it.
Here is a screen shot of the new message window in Yahoo email notice the link to enable the bcc line.

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