Which advance made a network of railroad lines possible? a. the air brake c. the convertible berth b. a standard gauge d. the dining car Which advance made a network of railroad lines possible? a. the air brake
c. the convertible berth
b. a standard gauge
d. the dining car

pls help

Put these events in the correct order #1-4. cause: world war 1 caused heavy casualties and property damage throughout europe. many people barely had enough food to eat or coal to stay warm. what happened next? question 1 options: russia, now led by lenin, became the first communist nation in history. communism soon spread to many small countries near russia, and eventually spread to cuba, china, and vietnam. led by vladimir lenin, a group called the bolshevik party gained the support of the people and overthrew russia’s monarchy, killing czar nicholas ii and his family. russian citizens, who were starving and poor, became angry at the ruling class who held all of the nation’s wealth. (write them in order of which they happened)