Which of the following represents the decibel level of rustling of tree leaves in normal circumstance?

उत्तर दाखवा आणि स्पष्टीकरण

उत्तर: (B) 20 dB

स्पष्टीकरण

Rustling leaves are about 20 dB (a whisper is about 30 dB, normal conversation about 60 dB).