Relationship

Q. We are examining the relationship between the number of cold calls a broker makes and the number of accounts the firm as a whole opens. We have determined that the correlation coefficient is equal to 0.70, based on a sample size of 16 observations. Is this relationship statistically significant at a 10% level of significance, and why or why not? The relationship is: A) not significant, the critical value exceed the t-statistics by 1.91 B) significant, the t-statistics exceeds the critical value by 3.67 C) not significant, the critical value exceed the t-statistics by 4.21 D) significant, the t-statistics exceeds the critical value by 1.91. The solution uses n-2 df… can you please why and also how u get it.

I completely forgot that there is something called as Spearman Rank Correlation Coefficient.