4. [-l4 Points] DETAILS DEVORESTAT9 4.5.0765. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER An article suggests the lognormal distribution as a model for SO2 concentration above a certain forest. Suppose the parameter values are pa = 2.1 and a = 0.7. l USE SALT (a) What are the mean value and standard deviation of concentration? (Round your answers to three decimal places.) mean E standard deviation :] (b) What is the probability that concentration is at most 10? Between 5 and 10? (Round your answers to four decimal places.) between 5 and 10 :] You may need to use the appropriate table in the Appendix of Tables to answer this question. Need Help? 5. [-/7 Points] DETAILS DEVORESTAT9 4.5.081 .5. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER Sales delay is the elapsed time between the manufacture of a product and its sale. According an article it is quite common for investigators to model sales delay using a lognormal distribution. For a particular product, the cited article proposes this distribution with parameter values ,u = 2.02 and 02 = 0.07 (here the unit for delay is months). IQ us: SALT (a) What are the variance and standard deviation of delay time? (Round your answers to two decimal places.) variance :] months2 standard deviation :] months (b) What is the probability that delay time exceeds 12 months? (Round your answer to four decimal places.) :1 (c) What is the probability that delay time is within one standard deviation of its mean value? (Round your answer to four decimal places.) :1 (d) What is the median of the delay time distribution? (Round your answer to two decimal places.) mum: i: (e) What is the 99th percentile of the delay time distribution? (Round your answer to two decimal places.) (1') Among 10 randomly selected such items, how many would you expect to have a delay time exceeding 5 months? (Round your answer to three decimal places.) You may need to use the appropriate table in the Appendix of Tables to answer this question. Neuzl Help