Environmental Protection Daily Tip – March 20: Reward of 5 points for participation, plus another 5 points for answering 5 questions correctly
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Multiple-choice question: The main sources of noise include traffic noise, industrial noise, construction noise, and social noise. The sound level at which the human ear begins to feel pain is called the pain threshold, and it is ( ) decibels. A 60 B 90 C 120 D 140 c
The main sources of noise include traffic noise, industrial noise, construction noise, and social noise. The sound level at which the human ear begins to feel pain is called the pain threshold, and it is (C) decibels. A 60 B 90 C 120 D 140
The main sources of noise include traffic noise, industrial noise, construction noise, and social noise. The sound level at which the human ear begins to feel pain is called the pain threshold, and it is (C) decibels. A 60 B 90 C 120 D 140
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