Question 9 < > 6.2 The Standard Normal Distribution Table: Z-score and Probability A manufacturer knows that their items have a normally distributed lifespan, with a mean of 7.6 years, and standard deviation of 1.5 years. If you randomly purchase one item, what is the probability it will last longer than 4 years? a.) The Z-score = (Round to 2 decimal places) b.) The probability is (Round to 4 decimal places)