A
B
69 dB
B
A
A
B
A
B
6 dB
B
A
69 dB
B
A
B
A
7 dB
B
A
6 dB
C
A
72 dB
B
A
70 dB
B
A
7 dB
C
A
C
A
7 dB
B
A
C
A
72 dB
B
A
71 dB