Tinterval Refer to the accompanying data display that results from a sample (13.046,22.15) of airport data speeds in Mbps. Complete parts (a) through (c) below. Click the icon to view a t distribution table. x = 17.598 n = 50 Sx 16.01712719 a. What is the number of degrees of freedom that should be used for finding the critical value ta/2? df=