A
B
6 dB
A
B
C
A
72 dB
B
A
72 dB
D
B
7 dB
B
B
B
B
A
B
B
A
7 dB
B
A
C
C
7 dB
B
B
6 dB
A
A
71 dB
A
A
C
C
B
B
71 dB
A
A
7 dB
B
A
6 dB
B
A
B
A
6 dB
A
A
7 dB
B
A
7 dB
A
A
C
A
7 dB