The Rockwell hardness index for steel is determined by pressing a diamond point into the steel and measuring the depth of penetration. For 50 specimens of an alloy of steel, the Rockwell hardness index averaged 62 with standard deviation 8. The manufacturer claims that this alloy has an average hardness index of at least 64 Refer to the previous questions. Find the sample size necessary to have Power of .98 when the true Rockwell hardness is 60.

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