What are the two ways that a us constitutional amendment can be approved?

pls answer !
!

How did the completion of the transcontinental railroad change the lives of american citizens? a-it increased the wealth of all americans and enabled them to travel more.b-it made cross-country travel too expensive for ordinary americans.c-it decreased the safety of americans who moved to settle the plains.d-it shortened travel time between the east and west for all americans.

What was the historic border between the united states and mexico?

During the age of imperialism, suez canal connected which two bodies of water?