How did washington dc become the nations capital

Ineed answers 5 and 6 on my social studies homework reply to this question i posted

Based on the map, which statement best describes the neighborhood of washington heights? (2 points) washington heights is a gated community. people of many ethnicities live in washington heights. restrictive covenants prevent most people from living in washington heights. dominicans have gentrified washington heights. washington heights is a dominican enclave.

Space is not completely empty. there are small particles in space. what happens when these particles come together?