Declaration: 
nDistriQuantile (p: double): double; 
The function nDistriQuantile
returns the quantile value of the standard normal distribution for a given probability p. The parameter p may take any value in the open interval (0,1). If nDistriQuantile is called using an invalid value of p a value of 0.0 is returned.

Hint: 
The calculated value is exact to about 8 decimal places. 
