s
h
o
w
r
A
B
≈
6
.
6
2
B
C
≈
6
.
2
2
A
C
≈
7
.
8
0
r
≈
1
.
9
2
s
≈
1
0
.
3
2
a
r
e
a
(
A
B
C
)
≈
1
9
.
8
5
r
×
s
≈
1
9
.
8
5