Nylon-6,6 is a high-strength engineering polymer widely used to manufacture mechanical components such as gears, wear strips, and bushings.
Nylon-6,6 has a melting point of 260∘C260^\circ\text{C}260∘C.
A cast iron alloy traditionally used to manufacture heavy-duty gears has a melting point of 1300∘C1300^\circ\text{C}1300∘C.
Calculate the ratio of the melting point of Nylon-6,6 to the melting point of the cast iron alloy. Express the ratio in its simplest integer form, 1:n1 : n1:n.
In the past, industrial gears and bushings were almost exclusively made of metals such as cast iron or bronze. Suggest two reasons why engineering polymers like Nylon-6,6 are now often preferred over these metals for modern mechanical components.