D
B
75 dB
A
B
75 dB
B
A
75 dB
B
A
75 dB
A
B
75 dB
D
B
75 dB
B
A
B
D
B
75 dB
A
B
75 dB
B
A
75 dB
A
B
C
B
75 dB