Two suppliers manufacture a plastic gear used in a laser printer. The impact strength of these gears measures in foot-pounds is an important characteristic. A random sample of 10 gears from supplier 1 results in x₁ = 290 and s₁ = 12 while another random sample of 16 gears from the second supplier results in x₂ = 321 and s₂ = 22. Is there evidence to support the claim that supplier 2 provides gears with higher mean impact strength. Use a =0.04, and assume that both populations are normally distributed with equal variances.

Construction in civil engineering demands high strength, durability, and longevity. These targets can be achieved by better design and analysis, along with the correct choice of materials. Different materials have different properties and hence, they res…