Which country first discovered petrol

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 result of delegates from the democratic party not being able to nominate a candidate in 1860

Brainliestttme : describe the following event: increase in islamic extremism in the middle east