The amount of shaft wear (.0001 in.) after a fixed mileage was determined for each of n = 8 internal combustion engines having copper lead as a bearing material, resulting in a sample mean of 3.72 and s = 1.25. assuming that the distribution of shaft wear is normal with mean μ, use the appropriate test at level .05 to test h0 : μ = 3.50 versus hα : μ > 3.50. state any assumption you have made if necessary.