12. [1.1 2/2.81 Points] DETAILS PREVIOUS ANSWERS DEVORESTAT9 7.3.038. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER Ultra high performance concrete (UHPC) is a relatively new construction material that is characterized by strong adhesive properties with other materials. The article "Adhesive Power of Ultra High Performance Concrete from a Thermodynamic Point of View"t described an investigation of the intermolecular forces for UHPC connected to various substrates. The following work of adhesion measurements (in mJ/mz) for UHPC specimens adhered to steel appeared in the article. 107.1 109.5 107.4 106.8 108.1 (a) Is it plausible that the given sample observations were selected from a normal distribution? 0 It's plausible that the distribution could be normal. 0 It's not plausible that the distribution could be normal. J (b) Calculate a twosided 95% confidence interval for the true average work of adhesion for UHPC adhered to steel. (Round your answers to two decimal places.) (SISlmJ/mz Does the interval suggest that 108 is a plausible value for the true average work of adhesion for UHPC adhered to steel? O The interval suggests that 108 is a possible value for the true average. 0 The interval doesn't suggest that 108 is a possible value for the true average. W Does the interval suggest that 110 is a plausible value for the true average work of adhesion for UHPC adhered to steel? O The interval suggests that 110 is a possible value for the true average. 0 The interval doesn't suggest that 110 is a possible value for the true average. v (c) Predict the resulting work of adhesion value resulting from a single future replication of the experiment by calculating a 95% prediction interval. (Round your answers to two decimal places.) (SISlmJ/mz Compare the width of this interval to the width of the CI from (b). O The CI is wider than the PI. 0 The PI is wider than the c1. 0 The two intervals are the same width. w? (d) Calculate an interval for which you can have a high degree of confidence that at least 95% of all UHPC specimens adhered to steel will have work of adhesion values between the limits of the interval. (Round your answers to two decimal places.) (SISlmJ/mz You may need to use the appropriate table in the Appendix of Tables to answer this question. Need Help? _' 13. [0/2.81 Points] I DETAILS l l PREVIOUS ANSWERS l DEVORESTAT9 7.4.0425. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER Determine the values of the following quantities. (Round your answers to two decimal places.) IA USE SALT 2 (a) X 0.05,15 23.684 x 2 (b) X 005,30 2 (C) I 0.025, 30 2 (d) X 0.01, 30 2 (e) X 095,30 2 (f) X 0.975, 30 You may need to use the appropriate table in the Appendix of Tables to answer this question. Need Help? _' Submit Answer 14. [1 .41/2.81 Points] DETAILS PREVIOUS ANSWERS DEVORESTAT9 7.4.043.MI.S. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER Determine the following: m USE SALT (a) The 95th percentile of the chi-squared distribution with 11 = 5 (Round your answer to three decimal places.) 11.070 .2 (b) The 5th percentile of the chi-squared distribution with 1) = 5 (Round your answer to three decimal places.) 0.831 x (c) P(10.283 s ){2 5 35.479), where )(2 is a chi-squared rv with v = 21 (Round your answer to two decimal places.) 0.80 x (d) P()(2 49.802), where x2 is a chi-squared rv with 11 = 35 (Round your answer to two decimal places.) 0.11 y You may need to use the appropriate table in the Appendix of Tables to answer this question. 10. [1 .61/2.81 Points] DETAILS PREVIOUS ANSWERS DEVORESTAT9 7.3.033. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER An article contained the following observations on degree of polymerization for paper specimens for which viscosity times concentration fell in a certain middle range: 415 421 422 422 425 426 431 434 437 439 446 446 449 451 454 461 465 (a) Construct a boxplot of the data. 0 420 430 440 450 460 O 420 430 440 450 460 o 420 430 440 450 460 420 430 440 450 $0 Comment on any interesting features. (Select a I that apply.) The data appears to be centered near 428. C] There is one outlier. The data appears to be centered near 438. Q There is little or no skew. There are no outliers. O The data is strongly skewed. X (b) Is it plausible that the given sample observations were selected from a normal distribution? 0 Yes ONo J (c) Calculate a two-sided 95% confidence interval for true average degree of polymerization. (Round your answers to two decimal places.) (SIS) 15. [l2.81 Points] DETAILS DEVORESTAT9 7.4.044. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER The amount of lateral expansion (mils) was determined for a sample of n = 8 pulsedpower gas metal arc welds used in LNG ship containment tanks. The resulting sample standard deviation was s = 2.87 mils. Assuming normality, derive a 95% CI for 0'2 and for a. (Round your answers to two decimal places.) (SIGNS You may need to use the appropriate table in the Appendix of Tables to answer this question. Need Help? 16. [0.95/2.85 Points] _ETAILS _REVIOUS ANSWERS DEVORESTAT9 7.4.045. _Y NOTES _SK YOUR TEACHER _RACTICE ANOTHER ctrical- -discharge machining (WED process used to manufacture condu tive hard met components. It uses continuously moving wire that serves as an electrode. Coating on the wire electrode allows for cooling of the wire electrode core and provides an improved cutting performance. An article gave the following sample observations on total coating layer thickness (in pm) of eight wire electrodes used for WEDM. 22 16 29 35 42 25 25 26 Calculate a 99% CI for the standard deviation of the coating layer thickness distribution. (Round your answers to two decimal places.) (x .x) Is this interval valid whatever the nature of the distribution? Explain. O Yes, there are enough data points for this interval to be valid. 0 No, validity of this interval requires that coating layer thickness be, at least approximately, normally distributed. -/ You may need to use the appropriate table in the Appendix of Tables to answer this question. Need Help? 11. [0.57/2.81 Points] DETAILS PREVIOUS ANSWERS DEVORESTAT9 7.3.035. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER Silicone implant augmentation rhinoplasty is used to correct congenital nose deformities. The success of the procedure depends on various biomechanical properties of the human nasal periosteum and fascia. An article reported that for a sample of 13 (newly deceased) adults, the mean failure strain (%) was 26.0, and the standard deviation was 3.2. (a) Assuming a normal distribution for failure strain, estimate true average strain in a way that conveys information about precision and reliability. (Use a 95% confidence interval. Round your answers to two decimal places.) (Segue) (b) Predict the strain for a single adult in a way that conveys information about precision and reliability. (Use a 95% prediction interval. Round your answers to two decimal places.) (SeeCJe) How does the prediction compare to the estimate calculated in part (a)? O The prediction interval is much narrower than the confidence interval in part (a). C) The prediction interval is the same as the confidence interval in part (a). O The prediction interval is much wider than the confidence interval in part (a). v You may need to use the appropriate table in the Appendix of Tables to answer this question. Need Help