237 / 1173
S
=
1
−
1
−
e
−
D D
0
(
)
n
P
(0 hits on a target)
=
e
-D/D
0
P
(≥1 hit on a target)
= 1 –
e
-D/D
0
P
(≥1 hit on
n
targets)
= (1 –
e
-D/D
0
)
n
P
(not
all
targets hit)
= 1 – (1 –
e
-D/D
0
)
n
D
q
=
D
0
log
e
n
5.4 = 1.6 × 3.4