Exam (elaborations)
ILE Exam Hearing Aids Correct 100%
- Module
- Institution
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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