This function is the inverse of the normal distribution probability function. Given a probability and a tail template from the tail menu, this function will return the z-score bounds.
The tail menu is used to select an area under the normal curve.
Percentile is the probability of a normally-distributed event occuring in an area under the normal curve.
The result is the z-score of the bounds of the area that would provide an area with a probability given in the percentile box.