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