15-
11 ■111 >11 ‘11■■1*i1■Vii1■*■i1■1■i1'1 • i"111 ■ ■
6.5 6.0 5.5 5.0 4.5
n | iii * i m rprrrrrm i j i i i i [ r111 j i1 i \ 11111 j 1111 ym 1111111 j n i 11 rrrrfn i rym i ptttj
4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0
ppm