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A population has a mean of 300 and a standard deviation of 80. Suppose a sample of size 125 is selected and (E is used to estimate 11. Use z-table. a. What is the probability that the sample mean will be within +/- 3 of the population mean (to 4 decimals)? (Round 2 value in intermediate calculations to 2 decimal places.) 0.3255 b. What is the probability that the sample mean will be within +/- 15 of the population mean (to 4 decimals)? (Round 2 value in intermediate calculations to 2 decimal places.)