need help with 11- 21 please

11. [-/2 Points] DETAILS BBBASICSTAT8 7.2.050.NVA MY NOTES PRACTICE ANOTHER Let z be a random variable with a standard normal distribution. Find the indicated probability. (Round your answer to four decimal places.) P(-0.77 s z s 3.24) = Shade the corresponding area under the standard normal curve. 0-3 -2 -1 0 1 2 3 0-3 -2 -1 0 1 2 0-3 -2 -1 0-3 -2 -1 2 12. [-/1 Points] DETAILS BBBASICSTAT8 7.3.002. MY NOTES PRACTICE ANOTHER Suppose 30% of the area under the standard normal curve lies to the right of z. Is z positive or negative? O positive negative Need Help? Read It13. [-/1 Points] DETAILS BBBASICSTAT8 7.3.006.NVA MY NOTES PRACTICE ANOTHER Assume that x has a normal distribution with the specified mean and standard deviation. Find the indicated probability. (Round your answer to four decimal places.) u = 15.5; 0 = 3.8 P(10 S x S 26) = 14. [-/2 Points] DETAILS BBBASICSTAT8 7.3.016.NVA MY NOTES PRACTICE ANOTHER Find z such that 3.6% of the standard normal curve lies to the left of z. (Round your answer to two decimal places.) Z = Sketch the area described. O 0 Z O 0 Z O Z 0 O Z 015. [-/2 Points] DETAILS BBBASICSTAT8 7.3.023.NVA MY NOTES PRACTICE ANOTHER Find the z value such that 92% of the standard normal curve lies between -z and z. (Round your answer to two decimal places.) Z = Sketch the area described. O -Z 0 Z O -Z 0 0 Z O -Z 0 Z15. lI3 Points] EBBASICSTATG 7.3.028.MI.NVA PRACTICE ANOTHER Police response time to an emergency call is the difference between the time the call is first received by the dispatcher and the time a patrol car radios mat it has arrived at the scene. Over a long period of time, it has been determined that the police response time has a normal distribution with a mean of 9.2 minutes and a standard deviation of 21 minutes. For a randomly received emergency call, nd the following probabilities. (Round your answers to four decimal places.) (a) the response time is between 5 and 11 minutes (b) the response time is less than 5 minutes (c) the response time is more than 11 minutes Need Help? 17. Hz Points] EBEASICSTATS 7.R.023.NVA PRACTICE ANOTHER Express Courier Service has found that the delivery time for packages is normally distributed, with mean 13 hours and standard deviation 2 hours. (a) For a package selected at random, what is the probability that it ill be delivered in 18 hours or less? (Round your answer be four decimal places.) (b) What should be the guaranteed delivery time on all packages in order to be 90% sure that the package will be delivered before this time? (Hint: Note that 10% of the packages will be delivered at a time beyond the guaranteed time period.) (Round your answer to one decimal place.) hr 18. [-/6 Points] DETAILS BBBASICSTAT8 7.5.006.MI.NVA MY NOTES PRACTICE ANOTHER Suppose x has a distribution with a mean of 70 and a standard deviation of 51. Random samples of size n = 36 are drawn. (a) Describe the x distribution and compute the mean and standard deviation of the distribution. x has ---Select-- v distribution with mean x = and standard deviation ox =[ (b) Find the z value corresponding to x = 53. Z = (c) Find P(x