How do i turn up the volume so I can hear the person talking on the other end of the phone?

I can't hear the person I called talking on my phone. How do I turn up the volume so I can hear?

from Android Forums at AndroidCentral.com - Ask a Question //forums.androidcentral.com/ask-question/758501-how-do-i-turn-up-volume-so-i-can-hear-person-talking-other-end-phone-new-post.html
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