已知L1=85dB,L2=85dB,则合成声压级L1+2是()dB。A、86B、87C、88D、90

已知L1=85dB,L2=85dB,则合成声压级L1+2是()dB。

  • A、86
  • B、87
  • C、88
  • D、90

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