In a study of maternal cigarette smoking and bone density in newborns, 77 infants of mothers who smoked has a mean bone mineral content of 0.098 g/cm³ (s₁ = 0.026 g/cm³). The 161 infants whose mothers did not smoke has a mean bone mineral content of 0.095 g/cm³ (s₂ = 0.025 g/cm³).

a)Calculate the 95% confidence interval for ₁ - ₂.

b)Based on the confidence interval you just calculated, would you reject or retain H₀: ₁ - ₂ = 0 at =0.05?