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 2.3GPa, respectively. Suppose the distribution is normal. (Round your answers to four decimal places.) (a) Calculate P(74x76) when n=25. (b) How likely is it that the sample mean diameter exceeds 76 when n=36 ? You may need to use the appropriate table in the Appendix of Tables to answer this