Find the value (s) for each of the f cases. Round your answers to 3 decimal places. Enter negative values as a Upper tal area of 025 with 12 degrees of freedom is a. Upper tail area of 0.25 with 12 degrees of freedom is .
b. Lower tail area of .005 with 55 degrees of freedom is
c. Upper tail area of .20 with 30 degrees of freedom is
d. where 98% of the area falls between these two t-values with 20 degrees of freedom.