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An office manager has received a report from a consultant that includes a section on equlpment replacement. The report indicates that scanners have a service life that is normally distributed with a mean of 49 months and a standard deviation of 4 months. On the basis of this information, determine the proportion of scanners that can be expected to fail in the following time periods: Use Table A and Table B. a. Before 42 months of service. (Round 2 values to 2 decimal places, probability calculations to 4 decimal places and your final answer to 4 decimal places.) b. Between 48 and 54 months of service. (Round z values to 2 decimal places, probability calculations to 4 decimal places and your final answer to 4 decimal places.) c. Within \pm 2 months of the mean life. (Round z values to 2 decimal places, probability calculations to 4 decimal places and your final answer to 4 decimal places.)