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2. If x is a binomial random variable with n=10 and p=0.8, the mean value of x is______ 3. According to the central limit theorem, for samples of size 64 drawn from a population with µ =800 and σ = 56, the standard deviation of the sampling distribution of sample means would equal ______ 4. Life tests performed on a sample of 13 batteries of a new model indicated: (1) an average life of75 months, and (2) a standard deviation of 5 months. Other battery models, produced by similar processes, have normally distributed life spans. The 98% confidence interval for the population mean life of the new model is _________ 5. A large national company is considering negotiating cellular phone rates for its employees Human Resource department would like to estimate the proportion of its employee population who own an Apple iPhone. A random sample of size 250 is taken and 40% of the sample own and iPhone.. The 95% confidence interval to estimate the population proportion is _______ 6. The number of bags arriving on the baggage claim conveyor belt in a 3 minute time period would best be modeled with the ________ 7. The weight of a USB flash drive is 30 grams and is normally distributed. Periodically, quanlity control inspectors at Dallas Flash Drives randomly select a sample of 17 USB flash drive. If the mean weight of the USB flash drives is too heavy or too light the machinery is shut down for adjustment; otherwise, the production process continues. The last sample showed a meanand standard deviation of 31.9 and 1.8 grams, respectively. Using a = 0.10, theappropriate decision is_______ 8. Elwin Osbourne, CIO at GFS, Inc., is studying employee use of GFS e-mail for non-business communications. He plans to use a 95% confidence interval estimate of the proportion of e-mail messages that are non-business; he will accept a 0.05 error. Previous studies indicate that approximately 30% of employee e-mail is not business related. Elwin should sample _______ e-mail messages