Which samples show unequal variances? Use = .10 in all tests. Show the critical values and degrees of freedom clearly and illustrate the decision

Which samples show unequal variances? Use α = .10 in all tests. Show the critical values and degrees of freedom clearly and illustrate the decision rule.
a. s1 = 10.2, n1 = 22, s2 = 6.4, n2 = 16, two-tailed test
b. s1 = 0.89, n1 = 25, s2 = 0.67, n2 = 18, right-tailed test
c. s1 = 124, n1 = 12, s2 = 260, n2 = 10, left-tailed test