1. [-/2 Points] DETAILS BBBASICSTAT8 8.1.005. MY NOTES True or false? A larger sample size produces a longer confidence interval for u. O False. As the sample size increases, the maximal error increases, resulting in a shorter confidence interval. False. As the sample size increases, the maximal error decreases, resulting in a shorter confidence interval. O True. As the sample size increases, the maximal error decreases, resulting in a longer confidence interval. O True. As the sample size increases, the maximal error increases, resulting in a longer confidence interval. Need Help? Read It 2. [-/2 Points] DETAILS BBBASICSTAT8 8.1.006. MY NOTES True or false? If the original x distribution has a relatively small standard deviation, the confidence interval for u will be relatively short. False. As o decreases, E increases, resulting in a longer confidence interval. True. As o decreases, E increases, resulting in a shorter confidence interval. O False. As o decreases, E decreases, resulting in a longer confidence interval. True. As o decreases, E decreases, resulting in a shorter confidence interval. Need Help? Read ItBBBASICSTAT8 8.1 .015. PRACTICE ANOTHER Allen's hummingbird (Selasphorus sasin) has been studied by zoologist Bill Alther.+ Suppose a small group of 20 Allen's hummingbirds has been under study in Arizona. The average weight for these birds is )7 = 3.15 grams. Based on previous studies, we can assume that the weights of Allen's hummingbirds have a normal distribution, with a = 0.40 gram. 3. [-112 Points] (a) Find an 80% confidence interval for the average weights of Allen's hummingbirds in the study region. What is the margin of error? (Round your answers to two decimal places.) lower limit upper limit margin of error (b) What conditions are necessary for your calculations? (Select all that apply.) T a is known T normal distribution of weights T n is large 0' is unknown T uniform distribution of weights (c) Interpret your results in the context of this problem. \" The probability that this interval contains the true average weight of Allen's hummingbirds is 0.20. '\\ The probability that this interval contains the true average weight of Allen's hummingbirds is 0.80. We are 20% condent that the true average weight of Allen's hummingbirds falls within this interval. '\\ We are 80% condent that the true average weight of Allen's hummingbirds falls within this interval. (d) Find the sample size necessary for an 80% condence level with a maximal margin of error E = 0.06 for the mean weights of the hummingbirds. (Round up to the nearest whole number.) hummingbirds Need Help? 4. [-I12 Points] - BBBASICSTAT8 8.1.016.MI. PRACTICE ANOTHER Overproduction of uric acid in the body can be an indication of cell breakdown. This may be an advance indication of illness such as gout, leukemia, or lymphoma.t Over a period of months, an adult male patient has taken ve blood tests for uric acid. The mean concentration was x = 5.28 mg/dl. The distribution of uric acid in healthy adult males can be assumed to be normal, with o' = 1.75 mg/dl. (3) Find a 95% condence interval for the population mean concentration of uric acid in this patient's blood. What is the margin of error? (Round your answers to two decimal places.) lower limit upper limit margin of error (b) What conditions are necessary for your calculations? (Select all that apply.) uniform distribution of uric acid a is known normal distribution of uric acid n is large ' a is unknown (c) Interpret your results in the context of this problem. We are 5% condent that the true uric acid level for this patient falls within this interval. ' ' We are 95% condent that the true uric acid level for this patient falls within this interval. The probability that this interval contains the true average uric acid level for this patient is 0.05. ' \\ The probability that this interval contains the true average uric acid level for this patient is 0.95. (d) Find the sample size necessary for a 95% condence level with maximal margin of error E = 1.12 for the mean concentration of uric acid in this patient's blood. (Round your answer up to the nearest whole number.) blood tests Need Help? 5. [-16 Points] WAS BBBASICSTAT8 8.2.013. | PRACTICE ANOTHER The method of tree ring dating gave the following years A.D. for an archaeological excavation site. Assume that the population ofx values has an approximately normal distribution. 1250 1201 1285 1264 1268 1316 1275 1317 1275 (a) Use a calculator with mean and standard deviation keys to find the sample mean year )7 and sample standard deviation 5. (Round your answers to the nearest whole number.) A.D. yr In >5. No;np> Sand nq5andnq>5. Need Help