Til

50} 137.5 — 137.5 > 87. ae
37.5al

©

COUNTS / MINUTE (RELATIVE)
Ol
>
hm

CALCULATED BACKGROUND

©

arAke

Yo

oO

LS81a0s

°

1lOr

°0

Oo
lOO

200

Jo
500
300 _ | 400

|

600

2 (om?)

491 Rev.DC
|“Fig. eTeR:Stevenson
and
Authors:

!

| a

P.C.
H.C. Hicks

Select target paragraph3