When do you use the Excel formulas and how do you use the formulas: T.INV, T.Dist.2t, Stdev.s and Stdev.P, VAR.P and VAR.S

T.INV= Find t* for CI, ex: 95% confidence interval +2,5% on each tail=0,975. Write that first and then take n-1. Example: T.INV(0,975;19). T.Dist.2t= Find p-value for hypothesis testing. For example if a excersize is testing 5% significant level. We do the test statistic and get a value, ex, 2,04. We then use this value in the formula and add n-1 to get degree of freedom. Example: T.Dist.2t( 2,04;19). The value we get we set i percentage. Ex: 0,0077=0,77%. The value is smaller than 5% so we reject the hypothesis. Stdev.s: Find adjusted sample deviation, when variance is unknown. You just drag the values to get the s. St dev. p: To get standard deviation. You just drag the values to get st dev. Var.p: Find variance. Just drag the values to get variance. Var.s: Find adjusted sample variation. Just drag the values to get s^2