Proof im giving u all my points im wasting cause why not .. :)

The valve seat performs two functions: it provides a seal for the valve in the combustion chamber, and it provides a cool surface to carry heat away from the valve. most valves use a seating angle.

Briefly explain how one development from the period 1861 to 1865 not directly mentioned un the excerpts supports mcpherson's argument

According to the nebular theory, the planets formed from a process called . after our protosun formed, remaining dust and gas from the nebula collided, combined, and gravitated together to form the planets.