Exam (elaborations)
ILE Exam Hearing Aids Questions with 100% correct Answers
- Course
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Hand Cupped Behind Ear - ANSWER--first Hearing Aid -increased sound by 5-8db -included horns,trumpets, speaking tubes 1892 - ANSWER--carbon amplifiers patent by Alexander Bell -marketed until 1930;first patent for a telephone type hearing instrument 1920 - ANSWER-large vacuum tubes; not p...
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