Which concept is described in the theory proposed by Hess? Continents do not move.

Cool rock pushes through the crust.

Trenches are sites of seafloor spreading.

Mid-ocean ridges are sites of seafloor spreading.

Mid-ocean ridges are sites of seafloor spreading

Explanation:With time there is a change in the continental structure and the ocean surface and the sea floor spreading

assuming that by westerners you mean americans. that they were mean and controlling and abusive to its peasants.

explanation:

in 1897, pershing became a tactical officer at west point, and that's where he was given the nickname "black jack." pershing's first name is "john," for which "jack" is a nickname, and he was a white man who commanded black troops. hence "black jack".