Which ocean is the only one that is located on the oceanic type of Earth’s crust with its entire surface?

Which are two new oceans by the definition of IHO?

Please help

Which number shows the location of the united kingdom of great britain? 7 5 2 4

Distance that the transcontinental railroad covered from omaha to san francisco.

What empire controlled most of the middle east except for a few years between 1516 and 1917, where was the capital of this empire located and what was the geographic extent of this empire?