Hearing Loss
Read section 1.2 titled "Possible Causes of Hearing Loss." It begins on page 7 and ends on page 11. (15 minutes)
World Health Organization - 2015
Click https://drive.google.com/file/d/17RphnYjLgU0YJomrWtcb1fNHiUiTH1an/view?usp=sharing link to open resource.