3.1) The significance of the correlation coefficient

Given the dataset for the Na and Cl concentrations of pore fluids in soils from Nova Scotia that
you investigated last week;

A. Is the correlation coefficient significant at a 5% confidence interval? (critical 
     Spearman r for 71 samples is 0.27, t(0.95;69) = 1.680)
B. Is the Pearson correlation coefficient significant at the 2.5% confidence level?
     And what about the 0.5% level? What is the critical probability at which the 
     correlation is no longer significant?

Data

 CL         NA                CL         NA
10.6        9.4              18.6       15.2
18.5        9.4              32.3       21.2
44.5       23.1              12.9        8.3
13.2        8.6               8.6        6.3
29.8       10.9              21.9       11.9
38.5       17.4              14.8        7.6
20.9        8.0              39.0       30.8
 4.9        4.7              34.2       28.1
43.2       29.1              55.8       17.5
49.1       23.1              51.1       24.9
13.2       10.6              15.1        9.6
24.1       14.5              68.3       35.0
11.2       11.4              17.3       11.3
48.8       17.8              39.1       24.3
28.9       12.6              64.9       29.8
55.8       29.2              17.6       12.7
15.1        9.6              56.9       18.3
56.8       29.9              11.9       13.9
58.7       20.0               7.9        6.8
31.3       18.5              63.3       28.8
51.9       32.9              14.0        9.2
29.9       12.2              66.7       34.4
33.1       12.2              53.6       43.1
14.7        8.9              23.5       13.2
 8.3        6.0              34.2       14.0
 7.7        8.6              67.4       38.5
15.0        8.2              37.3       12.9
52.6       52.3              11.2        6.4
69.0       37.9              11.8        8.9
17.4       21.1               4.9        6.3
36.9       21.5               6.0        4.2
30.1       13.9              38.1       20.2
16.4       17.4              44.7       20.5
31.8       13.1              44.3       24.8
39.5       15.2              13.1       10.2
32.4       17.4