Radon is a colorless and odorless radioactive gas that can accumulate in residential homes. High levels of exposure can lead to health problems. Radon levels are measured in units of picocuries per liter (pCi / L). The recommended radon level is less than 4 pCi / L. A housing development has 110 residential homes. The homeowners association would like to estimate the average radon level in the development. Because it would be too expensive to measure every home, a random sample of 31 homes was selected to be tested, and the average radon level was found to be 1.3 pCi / L. Assume from past studies the population standard deviation of radon levels in homes is 0.5 pCi / L. Complete parts a and b below. a. Construct a 90% confidence interval to estimate the average radon level in the housing development. The 90% confidence interval to estimate the average radon level is ( pci/LpCi/L). (Round to two decimal places as needed.)X Construct a 95% confidence interval to estimate the population proportion with a sample proportion equal to 0.60 and a sample size equal to 250. Cumulative probabilities to the left of z Click the icon to view a portion of the Cumulative Probabilities for the Standard Normal Distribution table. SECOND DIGIT OF Z A 95% confidence interval estimates that the population proportion is between a lower limit of | | and an upper limit of . FIRST DIGIT OF Z 0.06 0.07 0.08 0.09 0.00 0.01 0.02 0.03 0.04 0.05 0.5160 0.5199 0.5239 0.5270 0.5319 0.5359 Round to three decimal places as needed.) 0.5000 0.5040 0.5080 0.5120 0.5398 0.5438 0.5478 0.5517 0.5557 0.5506 0.5636 0.5675 0.5714 0.5753 0.1 0.5948 0.5987 0.6026 0.6064 0.6103 0.6141 0.5793 0.5832 0.5871 0.5910 0.2 0.6331 0.6368 0.6406 0.6443 0.6480 0.6517 0.6179 0.6293 03 0.6217 0.6255 0.6628 0.6664 0.6700 0.6736 0.6772 0.6808 0.6844 0.6879 04 0.6554 0.6591 0.7190 0.7224 0.6915 0.6950 0.6985 0.7019 0.7054 0.7088 0.7123 0.7157 05 0.7389 0.74:22 D.7454 0.7486 0.7517 0.7549 0.7257 0.7357 0.6 0.7291 0.7324 0.761 1 0.7642 0,7673 0.7704 0.7734 0.7764 0.7794 0.7823 0.7852 O.7 0.7580 0.7993 0.8023 0.8051 08078 0.8106 0.8133 0.8 0.7881 0.7910 0.7939 0.7967 0.8264 0.8289 0.8315 0.8340 0.8365 0.8389 0.8159 0.8238 0.9 0.8186 0.8212 0.8554 0.8577 0.8599 0.8621 1.0 0.8413 0.8438 0.8461 0,8485 0.8508 0.8531 0.8686 0.8708 0.8729 0.8749 0.8770 0.8790 0.8810 0.8830 1.1 0.8643 0.8665 0.8962 0.8980 0.8097 0.9015 1.2 0.8849 0.8869 0.8388 0.8907 0.8925 0.8044 0.91 15 09131 0.9147 0.9162 0.9177 0.9049 0,9082 0.9099 1.3 0.9032 0,9066 0.9251 0.9265 0.9279 0.9292 0.9306 0.9319 1.4 0.9192 0.9207 0.9222 0.9236 0.9441 0.9345 0.9357 0.9370 0.9382 0.9304 0.9406 0.9418 0.9429 1.5 0.9332 0.9495 0.9505 0.9515 0. 9525 0.9535 0.9545 0.9452 0.0474 0.9484 1.6 0.9463 0.9599 0.9608 0.9616 0.9625 0.9633 1.7 0.9554 0.9564 0.9573 0.9582 0.9591 0.9699 0.9706 0.9641 0.9649 0.9656 0.9664 0.9671 0.9678 0.9686 0.9693 1.8 0.9750 0.9756 0,9761 0.9767 1.9 0.9713 0.9719 0.9726 0.9732 0.9738 0.0744 0.9793 0.9798 0.9803 0.9808 0.9812 0.9817 2.0 0.9772 0.9778 0.9783 0.9788 0.9821 0.9826 0.9830 0.9834 0.9838 0.9842 0.9846 0.9850 0.9854 0.9857 2.1 0.9881 0.9890 0.9875 0.9878 0.9884 0.0887 2.2 0.9861 0.9864 0.0868 0.9871 0.9909 0.991 1 0.9913 0.9916 2.3 0.9893 0.9896 0.9898 0.9901 0.9904 0.9906 0.9927 0.9929 0.9931 0.9932 0.9934 0.9936 2.4 0.9918 0.9920 0.9922 0.9925 0.9046 0.0948 09040 0.905 1 0.9952 25 0.9040 0.0941 0.9043 0.9045 0.0938 0.9956 0.9957 0.9959 0.9960 0.9961 0.9962 0.9963 0.9964 2.6 0.9953 0.9955 0.9967 0.9968 0.9969 0.9970 0.9971 0.9972 0.9973 0.9974 2.7 0.9965 0.9966 0.9974 0.9977 0.9978 0.9979 0.9970 0.9080 0.9981 28 0.9975 0.0976 0.9077 0.9985 0.9985 0.9986 0.9986 29 0.9981 0.9982 0.9982 0.9983 0.9984 0.9984 0.9988 0.9989 0.9989 0.9939 0.9990 0.9990 30 0.9987 0.9987 0.9987 0.9988 0.09 0.02 6.03 0.05 SECOND DIGIT OF Z FIRST DIGIT OF ZDetermine the sample size n needed to construct a 99% confidence interval to estimate the population mean for the following margins of error when o = 77. a) 5 b) 8 c) 10 X Cumulative Probabilities for the Standard Normal Distribution Click the icon to view a table of standard normal cumulative probabilities. a) n= (Round up to the nearest integer.) FIRST DIGIT OF Z SECOND DIGIT OF Z 0.00 0.01 0.02 0.03 0.04 0.05 0.06 0.07 0.08 0.09 10 0.8413 0.8438 0.8461 0.8485 0.8508 0.8531 0.8554 0.8577 0.8599 0.8621 1.1 0.8643 0.8665 0.8686 0.8708 0.8729 0.8749 0.8770 0.8790 0.8810 0.8830 1.2 0.8849 0.8869 0.8888 0.8907 0.8925 0.8944 0.8962 0.8980 0.8997 0.9015 1.3 0.9032 0.9049 0.9066 0.9082 0.9099 0.9115 0.9131 0.9147 0.9162 0.9177 14 0.9192 0.9207 0.9222 0.9236 0.9251 0.9265 0.9279 0.9292 0.9306 0.9319 1.5 0.9332 0.9345 0.9357 0.9370 0.9382 0.9394 0.9406 0.9418 0.9429 0.9441 1.6 0.9452 0.9463 0.9474 0.9484 0.9495 0.9505 0.9515 0.9525 0.9535 0.9545 1.7 0.9554 0.9564 0.9573 0.9582 0.9591 0.9599 0.9608 0.9616 0.9625 0.9633 1.8 0.9641 0.9649 0.9656 0.9664 0.9671 0.9678 0.9686 0.9693 0.9699 0.9706 1.9 0.9713 0.9719 0.9726 0.9732 0.9738 0.9744 0.9750 0.9756 0.9761 0.9767 2.0 0.9772 0.9778 0.9783 0.9788 0.9793 0.9798 0.9803 0.9808 0.9812 0.9817 2.1 0.9821 0.9826 0.9830 0.9834 0.9838 0.9842 0.9846 0.9850 0.9854 0.9857 2.2 0.9861 0.9864 0.9868 0.9871 0.9875 0.9878 0.9881 0.9884 0.9887 0.9890 2.3 0.9893 0.9896 0.9898 0.9901 0.9904 0.9906 0.9909 0.991 1 0.9913 0.9916 2.4 0.9918 0.9920 0.9922 0.9925 0.9927 0.9929 0.9931 0.9932 0.9934 0.9936 2.5 0.9938 0.9940 0.9941 0.9943 0.9945 0.9946 0.9948 0.9949 0.9951 0.9952 2.6 0.9953 0.9955 0.9956 0.9957 0.9959 0.9960 0.9961 0.9962 0.9963 0.9964 2.7 0.9965 0.9966 0.9967 0.9968 0.9969 0.9970 0.9971 0.9972 0.9973 0.9974 2.8 0.9974 0.9975 0.9976 0.9977 0.9977 0.9978 0.9979 0.9979 0.9980 0.9981 2.9 0.9981 0.9982 0.9982 0.9983 0.9984 0.9984 0.9985 0.9985 0.9986 0.9986 3.0 0.9987 0.9987 0.9987 0.9988 0.9988 0.9989 0.9989 0.9989 0.9990 0.9990 Print Done