    1; In their ‘study, researchers tested’..\  he. hearing. of '479.men between 20 and64  years -old who were: exposed ‘to- noise in their. °  jobs . a  ‘sentence 2: Barrenas ‘s teamitested the hearing”  of 479-men,,,aged ‘20.ta 64, who were ‘exposed  to-noise in their. jobs . a