Answer: Lubrication
Moving parts of early machines were able to run because of the application of a lubricant such as oil, vaseline or grease.
The history of lubrication has advanced into a discipline known as tribology, which studies interactions between the moving parts of a machine.
By studying friction, wear, and lubrication, engineers are able to design bearings that prolong the useful life of rotating machinery.
The answer is B. Most of the regions colonies were ruled by European nations
D) Set up the return of control of the canal to Panama in the year 2000.
T<span>he western conquests </span>began<span> in 533.</span><span>
Byzantium continued on for nearly a millennium until Constantinople itself fell in a siege carried out by the Ottoman Empire in 1453.</span>
Answer:
i dont know its your school work
Explanation: