Compute the value of the test statistic for the indicated test, based on the information given.
Testing H 0 : μ = 342 vs. H a : μ < 342, σ = 11.2, n = 40, x - = 339, s = 10.3
Testing H 0 : μ = 105 vs. H a : μ > 105, σ = 5.3, n = 80, x - = 107, s = 5.1
Testing H 0 : μ = − 13.5 vs. H a : μ ≠ − 13.5, σ unknown, n = 32, x - = − 13.8, s = 1.5
Testing H 0 : μ = 28 vs. H a : μ ≠ 28, σ unknown, n = 68, x - = 27.8, s = 1.3