B
A
6 dB
C
A
7 dB
C
A
A
A
69 dB
C
A
74 dB
B
A
7 dB
C
A
72 dB
A
A
C
A
7 dB
B
A
C
B
72 dB
C
A
72 dB
B
A
72 dB
C
A
72 dB