T.INV.2T(probability,deg_freedom) Returns the two-tailed inverse of the Student's tdistribution. - Probability: is the probability associated with the two-tailed Student's t-distribution, a number between 0 and 1 inclusive. - Deg_freedom: is a positive integer indicating the number of degrees of freedom to characterize the distribution. [In this course, we will not use "Excel's Descriptive Analysis Tool" for Confidence Interval computations.].