Use Table A.3 to find the critical value t2 needed to construct a confidence interval of the given level with the given sample size: a.

Use Table A.3 to find the critical value tα∕2 needed to construct a confidence interval of the given level with the given sample size:

a. Level 95%, sample size 15

b. Level 99%, sample size 22

c. Level 90%, sample size 63

d. Level 95%, sample size 2

4 0.271 0.741 1.533 2.132 5 0.267 0.727 1.476 2.015 6 0.265 0.718 1.440 1.943 7 0.263 0.711 1.415 1.895 2.365 8 0.262 0.706 1.397 1.860 2.306 9 0.261 0.703 1.383 1.833 2.262 2.776 3.747 4.604 2.571 3.365 4.032 2.447 3.143 2.998 3.499 2.896 3.355 3.833 2.821 3.250 3.690 4.297 5.598 7.173 8.610 4.773 5.893 6.869 3.707 4.317 5.208 5.959 4.029 4.785 5.408 4.501 5.041 4.781 10 0.260 0.700 1.372 1.812 2.228 11 0.260 0.697 1.363 1.796 2.201 2.764 3.169 3.581 2.718 3.106 3.497 4.144 4.025 4.437 4.587 12 0.259 0.695 1.356 1.782 2.179 2.681 3.055 3.428 3.930 4.318 13 0.259 0.694 1.350 1.771 2.160 2.650 3.012 3.372 3.852 4.221 14 0.258 0.692 1.345 1.761 2.145 2.624 2.977 3.326 3.787 4.140 20% 50% 80% 90% 95% 98% 99% 99.5% 99.8% 99.9% Confidence Level