An article in the journal Hazardous Waste and Hazardous Materials (Vol. 6, 1989) reported the results of an analysis ofthe weight of calcium in standard cement and cement dopedwith lead. Reduced levels of calcium would indicate that thehydration mechanism in the cement is blocked and wouldallow water to attack various locations in the cement structure.Ten samples of standard cement had an average weight percent calcium of = 90.0, with a sample standard deviation of s₁= 5.0, and 15 samples of the lead-doped cement had an average weight percent calcium of = 87.0 with a sample standard deviation of s₂ = 4.0. Is there evidence to support a claim that doping the cement with lead changes the mean weight of calcium in the cement?