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Young's modulus is a quantitative measure of stiffness of an elastic material. Suppose that for metal sheets of a particular type, its mean value and standard deviation are 75GPa and 1.8GPa, respectively. Suppose the distribution is normal. (Round your answers to four decimal places.) (a) Calculate A(74x76 ) when n=9. (b) How likely is it that the sample mean diameter exceeds 76 when n=25 ? You may need to use the appropriate table in the Appendx of Tables to answer this