1
.
Speaker
A
works
as
a
____________________
____________________
.
2
.
Speaker
B
works
as
a
____________________
____________________
.
3
.
Speaker
C
works
as
a
____________________
.
4
.
Speaker
D
works
as
a
____________________
.
5
.
Speaker
E
works
as
a
____________________
.
