Zn

Cr

Ni

Cu

Pb

p-Value

F-Ratio

P-Value

F-Ratio

P-Value

F-Ratio

P-Value

F-Ratio

P-Value

F-Ratio

0.0035

5.96

0.0337

3.41

0.0000

0.2127

0.0000

33.88

0.0007

8.05

Time

0.0000

22.20

0.0002

6.24

0.0001

7.27

0.0174

3.00

0.0000

9.94

Place